PHILOSOPHICAL TRANSACTIONS /P OF THE ROYAL SOCIETY OF LONDON. FOR THE YEAR MDCCCXXXVII. PART I. LONDON: PRINTED BY RICHARD AND JOHN E. TAYLOR, RED LION COURT, FLEET STREET. MDCCCXXXVII. ADVERTISEMENT. The Committee appointed by the Royal Society to direct the publication of the Philosophical Transactions, take this opportunity to acquaint the Public, that it fully appears, as well from the Council-books and Journals of the Society, as from repeated declarations which have been made in several former Transactions, that the printing of them was always, from time to time, the single act of the respective Secretaries till the Forty-seventh Volume ; the Society, as a Body, never interesting themselves any further in their publication, than by occasionally recommending the revival of them to some of their Secretaries, when, from the particular circumstances of their affairs, the Transactions had happened for any length of time to be intermitted. 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ROYAL MEDALS HIS MAJESTY KING WILLIAM THE FOURTH, in restoring the Foundation of the Royal Medals, graciously commanded a Letter, of which the following is an extract, to be addressed to the Royal Society, through His Royal Highness the Duke of Sussex, K.G., President : “ Windsor Castle, March 25, 1833. “ It is His Majesty’s wish, — “ First, That the Two Gold Medals, value of Fifty Guineas each, shall z>dx. S fr- \ r 2 x2 = //2 - 2 q = r2 - - 2 ) = ^ + 2 S x d x — r dr 2 2 rdr S x d x = — . — = d r. r 2 S d x = — dr •. S V' 1 — ■=. dr — dr — 0 whence this theorem : 7/1 the sines of three circular arcs are roots of the equation x3 -f- r x2 + — ] ) x — r = 0, the sum of the arcs is constant. I will give a numerical example of this theorem. The value of r is arbitrary. Suppose it to be = 3 — */\2 = — 0-4641016. MR. TALBOT’S RESEARCHES IN THE INTEGRAL CALCULUS. 5 The roots of the equation then have the following values : x = 05 = sin 30° = sin & y— 0-94565 = sin 71° 1' = sin 8 z = — 0-98154 = sin — (78° 59') = sin 8' ; and the theorem gives the sum of the arcs, or S 6 = const. The word sum is used in an algebraic sense, as including the case where one or more of the arcs are to be taken negatively , or its definition is S 6 = ± 6 ± 8 + 8\ The same ambiguity in the signs pervades the whole of this class of formulae. In the present instance S 6 = 0 + 8 — 8' = 30° + 7 1° T + 78° 59' = 180° the constant is a semicircle. Ex. 2. Let r = 0. x3 — x = 0 ; and the roots are x = 0 — sin 0° y — 1 = sin 90° z = — 1 = sin — 90° 6 = 0° 8 — 90° 8' ~ - 90° ; and the same formula gives, as before, 6 + 8 - 8' = 180°. A very extensive class of formulae respecting the arcs of the circle may be obtained in a similar manner, by applying the method more generally. Thus, if we make the supposition C1-] = «o + «i x + + an_xxn~\ where a0, av an_1 are constants, or any entire rational functions whatever of the variable v, we have an equation of 2 n dimensions, of which x is a root. If x — sin 0t, and the other roots are sin sin 6-s, sin 02n, then /dx and the other integrals = . . . 02n. And by a direct process we obtain the final equation S 6, or 6l3 + 62 + .... + $2n =/• v + const., f . v being an entire rational function of v. But since it is generally admitted that no combination of circular arcs can be equal to an algebraic quantity, I conclude that we have generally /• v = 0. 6 MR. TALBOT’S RESEARCHES IN THE INTEGRAL CALCULUS. If we consider the generality of the supposition [1.], which admits any number of arbitrary quantities, it certainly appears remarkable that this equation f. v = 0 should be always verified. §.3. Application to the Parabola. If the tangent at the vertex of a parabola be taken for the axis of abscissae, and the semiparameter = 1, then if x be the abscissa, the equation of the curve will be 2 y = x2, and the arc, which may be designated as arc x, —Jdx ■v'T + x1. The known value of this is [2.] Arc x = ^x\/l-{-x2 + ^ log (x -f- \/ 1 -{-x2). This is a function of x, the properties of which appear to have been hitherto little examined. I will establish two theorems concerning it, which are of considerable simplicity. Theorem I. — If three abscissae are the roots of the equation x3 — r x2 -f- + 1 ^ x — r = 0, the sum of the arcs equals the sum of the abscissae . Since each arc is greater than its corresponding abscissa, it is evident that the word sum is to be understood in an algebraic sense, or that at least one of the arcs must be taken negatively. Theorem II. — If three abscissae are the roots of the equation x3 - a x2 — a b — x + — 0, the sum of the arcs equals the product of the abscissae. This theorem is remarkable for its simplicity, when it is considered that it contains two arbitrary quantities, a and b, which, as it appears, may have any values. Demonstration of Theorem I. Put J 1 + 3C ■ "■ X 2 + v x -j- 1 : whence f 1 .1 x3 -f- 2 v x2 + (v2 + 1 ) x -f- 2 v — 0. Also S dx 1 -f- x2 = Sx2dx-\-vSxdx + S d x .’. S J* d x \/ \ + x2 = -f* J* S#. S x3 KJ tAj 10 The first term ^:fr- ~ —■ — p q -f- r in all equations. Here p = — 2 v q = v2 l r — — 2 v. MR. TALBOT’S RESEARCHES IN THE INTEGRAL CALCULUS. 7 S^3 — 8i? , „ , 9 , 2U3 — = —3 1- 2 v (v2 + 1) - 2 v = 3-. To find the value of the second term J* v S x d x, we have S x2 = p2 — 2 q = 4 v2 — (2 v2 + 2) = 2 r2 — 2 .\Sxdx = 2vdv and 2U3 f v & x d x = /' 2 v2 d v — 3 . Therefore these two terms destroy each other. Consequently we have simply s/* ^^1 + ^ = Sx + c. It appears by trial that C = 0, and the equation between the roots [1.] becomes, — V by writing for v its value — - — , x 3 — r x2 -\- -j- 1^ x — r = 0 .*. the sum of three arcs = S x = r. Q.E.D. Example . — Let us suppose r = 4 + 2 */2 = 6-82842 7. The three roots will be x = 1 # = 4-2042580 z = 1-6241690. Calculating the arcs accurately by the formula [2.], we have Arc x = 1-147793 Arc y — 10*156004 Arc 2 = 2-179773 In forming the sum we must notice that arc x and arc 2 are to be accounted nega- tive. Consequently we find by subtraction, Arc y = 10-156004 Arc x + Arc 2 = 3*327566 Sum = 6-828438 r = 6-828427 Error of calculation = 0-000011 Thus the calculation verifies the theorem with considerable exactness, and shows that no constant is required to be added to the integral. Since the sum of these three arcs is algebraic, and that each contains a logarithmic part, the sum of these three logarithms must be = 0 : for if not, it must be an alge- 8 MR. TALBOT’S RESEARCHES IN THE INTEGRAL CALCULUS. braic quantity, which is considered to be impossible. This is verified by calculation ; for s " 2 arc x = x */ 1 + x2 + log (x + J 1 + x2). Calling log (x + J l + x2) —f. x, we have fx = 0-881372 / .y = 2-143099 fz = 1*261722 fx + fz = 2-143094 2-143094 sum = 0-000005 This sum approaches zero very nearly. The quantities fx,fz are subtractive, being parts of 2 arc x and 2 arc z, which have been already shown to be so. Demonstration of Theorem II. Let v \/ 1 + x2 = n x2 + x + v, where n is a constant, ■ • ^ n ' 0 -r — u, and S^/l -{-x2 .dx = nSx2dx-\-Sxd x. — 2 . the term rS dx being omitted ; because, since S x = — is constant, the factor S dx = 0. The formula S x? — p3 — 3 p q 3 r gives S .r3 p3 ~T = T~ PI + r> / . 2 \ 2 .*. (observing that p is constant and = — —) S x2 d x — — d q -f- dr. Therefor the first term, or n S x2 d, x = 2 d q n d r. The formula 8 x2 — p2 — 2 q gives the second term, or S x d x — — d q .-. »S x2 d x + S x d x = d q -f- n dr, v S l + x2 . d x — dq + n d r. Now we have (omitting constants). -e or V S' n ir and , 2 7 2 v dv ; . dq — — dv ~ — , i n nr n dr = dv n d q n d r ~ — 2 v dv MR. TALBOT’S RESEARCHES IN THE INTEGRAL CALCULUS. 9 Therefore S*Jl+x2.dx = — S J* J\+x2 .dx= — ^ = r. Now writing n — , v — b, we have the equation in the form given above, viz. x9 — a x2 + — a b — x + ~ = 0 ; and therefore the theorem is demonstrated. Examples. Ex. 1 . Let a = 2 + J2, b — 1 , the roots of the equation are x — 1 i 5 1 y ~ 2 ' - 1 x — 1 .*. arc x — 1-147793 y — 3-906278 .*. arc y — 8'91 1399 2 = - 1-492065 .-. arc z = L935186 and Now we have .-. S x = 3-414213 = 2 + / 1 . /?2 O S d x \ / — — = — V 1 — x r 1 S x2 = p2 — 2 5 = r2 — ^ 1 (, e . r2 — 2^ = — l + S # c? a? = — - — r d r + e . r2 + 2 Also — S x dx — (1 -j - e2) dr. S d x — — dr 2 :.—$>xdx-\-$>dx = e2dr ■•■S dxy/'~**! = e2 dr = e*r + C. MR. TALBOT’S RESEARCHES IN THE INTEGRAL CALCULUS. 13 Or, if we suppose the radical to have a negative sign. S /‘»*v/1CT = c whence the following theorem : If three abscissae of an ellipse are roots of the equation the sum of the arcs = 2 Q — e2 r, Q being the quadrant of the ellipse. Ex. J. Let e — 0, or the ellipse be a circle ; the theorem then assumes this form : If three abscisses of a circle are roots of the equation the sum of the arcs is a semicircle ; the truth of which has been demonstrated pre- viously (vide page 4.). Fagnani’s theorem becomes illusory when e = 0: it is therefore interesting to ob- serve that the present theorem, on the contrary, has a real application to the circle. Ex. 2. Let e have any value, and r = 0 ; then the roots are which is therefore the value of the constant. Ex. 3. When x is not actually = 0, as in the last example, but has an indefinitely small value = u, it will be found that the values of y and z differ from 1 and — 1 by a quantity of the order of a2. But nevertheless the arcs which subtend these abscissae differ from a quadrant of the ellipse by a quantity of the order of a. This arises from the direction of the arc at the extremities of the axis being perpendicular to the abscissa, so that its increment is infinitely greater than that of the latter. It will be well to show the truth of the theorem in this case. When x = u we have (putting 1 - e2 = b2) For from these values we deduce y -{- z = 0, and thence (neglecting quantities of the order cJ3 ) x = 0 arc x = 0 = (1.) y = 1 arc y — Q = (2.) 2 = — 1 arc z = — Q = (3.) and the sum, viz. (l.)+(2.)-(3.)=2Q, 8 x -\ -y-\-z = x — u xy z = — - u. So that xy z are roots of 14 MR. TALBOT’S RESEARCHES IN THE INTEGRAL CALCULUS. u — 0, which agrees with the given form by putting r = — u. We have now to find the sum of the arcs. The arc subtending the abscissa (x = &>) may be considered as equal to it. The arc subtending the abscissa y differs from the elliptic quadrant by an arc which may be considered equal to the ordinate which corresponds to y. And the same with respect to z. Let y be the ordinate corresponding to y. The equation of the curve gives y = b s/ 1 -y2; but since r •Vi y 2 — b w o 5 and the arc subtending?/ = Q — The arc z has the same value. Therefore arc y -f arc z = 2 Q — b2 a ; adding arc x — we have Sum of arcs = 2 Q -j- e2 a, (or, since u = — r) — 2 Q — e2 r, in accordance with the theorem. Ex. 4. Let 1 — e2 = And also let r = 9 — 3 \/ ] 0 = — (MSGSSSl ; the roots of the equation x3 + r x2 + — 1 ^ x — r = 0, are x — 0*5 = sin 30° y — 0-98019 = sin 78° 34' z = — 0-99336 = sin 83° 24' Entering Legendre’s Table IX. with modulus e — \f ^ r — sin 54° 44' and these amplitudes, we find arc x — 0"5081 arc y = 1‘1 446 arc ^ = 1*1944 Sum = 2-8471 MR. TALBOT’S RESEARCHES IN THE INTEGRAL CALCULUS. 15 On the other hand we have 2 Q = 2 arc (90°) = 2*5224 ~ e2 r = 0*3246 2 Q - e2 r = 2-8470 Sum of arcs = 2-8471 Error = 00001 I will now indicate two other theorems respecting the sum of three elliptic arcs. // 1 — OC^" d X t ^ in the form f(l+ex)dx\J and assume 1 - p pQ t 1 e • \ — "x^\ a symmetrical = — . This gives (1 + e x) ( 2) & + t *2 — (v + *) x + v—rL — °> and the result which I find is, that if three abscissae are the roots of this equation, the sum of the corresponding arcs = 2 e v + C. II. We may put the integral in the form /* d x / (1 4- x) (1 — e* x2) J 1 + x v 1 — x 5 and assume ^ 1 + ^ ^ x e X ^ — v, whence + x1 — VAi- x + 0. The result which I find is, that if three abscissae are the roots of this equation, the sum of the arcs — 2 J v + C. These theorems respecting the sums of elliptic arcs appear to be some of the simplest which exist ; but an unlimited number of theorems of a higher order and more com- plicated nature are obtainable, the discussion of which would lead too far at present. Thus if we assume / 1 — e1 X2 n- 1 , \/ \ #2 ' — an-i x + an _ 2 xn “ -j- &c. where the coefficients are constants, or entire rational functions of v, we have an equation of 2 n dimensions, which gives the sum of 2 n elliptic arcs in terms of v. There is no difficulty, beyond the length of the operation, in deducing these theorems, as they are all obtainable by an uniform method. But it will be of im- portance to show the relation between them and the previously received doctrines respecting elliptic integrals as established by Legendre and others, the connexion between them not being at first sight very evident. 16 MR. TALBOT’S RESEARCHES IN THE INTEGRAL CALCULUS. § 6. Application to the Equilateral Hyperbola. /d x -^3 yj 1 -J- XAj which expresses the arc of the equilateral hyperbola, we may put 1 -j- — V X -j- 1 , whence x3 — v2 x — 2 v = 0, we have therefore 2 v — r, and making- this substitution, - x — r — 0. Also v' 1 -]- xA r , I X2 2 x x2 S V] +X\dx = -J-S — + S— . cL x x 2 Now we have and r „ d x r dr dr 2 x 2 ' r 2 ’ s — — 3_ _ _ r X r 1 r,dx d r — ~4 s 4/1 + x 2 *.d X = d r ~2 .dr 3 + 4 - ••• s f a/ 1 + X4 X2 . d x = so that if three abscissae of the equilateral hyperbola are roots of the equation r2 x3 — — x — r = 0, o the sum of the arcs = j r + C, which is the theorem which I originally met with concerning the hyperbolic arc*. It will be seen how very simply and directly we are conducted to it by the present method of investigation. Next let us suppose whence Put v — — y/ 1 -j- X* = V X3 + 1 . x3 — -}- ~~ — 0. V 1 V Philosophica Transactions, 1836, Part I. p. 185. MR. TALBOT’S RESEARCHES IN THE INTEGRAL CALCULUS. 17 /. x3 x — r = 0, and Therefore blit V 1 + x4 2 x l _ S i/l | ■y4. dx — - — + S^f, ~ d x dr as in the last example ; and S x2 — — S x dx — — dr r - S 1 + X3 d r ^.dx = ^-dr = -~dr 4 4 •• s / ^1+x\dx = ^-r + C. x * 4 This result therefore agrees with the last example, and gives the same theorem, but it supplies a different demonstration of it. We will now suppose V'l + x4 , , a , v o * A I "l X X xz a being a constant. This gives cd + 2 v X3 + 2 a x2 + v x + u2 — l — 0, and I find this result, that if three abscissae are roots of this equation, which may be written x3 — p x2 -f- q x — r — 0, then the sum of the arcs *0^ = p — — + const. =

bzte±.l p . 32 . I'y.2. Z'he lottery connected with die decomposing apparatus- 2. Z7ie decomposing apparatus. 3 A modification of Fig. 2. for obtaining die amalgams of die alcaZine metals. J3. The doited line in. Fig 3. shews the leyel of fluid cn. die funnel . aiove die mercury. JTJfasire. LONG-CONTINUED ELECTRIC CURRENTS OF LOW TENSION. 39 tity of electricity appearing to be by no means so important as a continuous and equable current. For similar reasons Mr. Mullins’s modification of Professor Daniell’s bat- tery was found equally objectionable ; added to which the currents evolved are liable to be materially affected by the admixture of the exciting fluids through the mem- branous partition, which always takes place sooner or later by endosmosmic action. 4. After several experiments I was induced to prefer the following apparatus, (which after all is but a slight modification of Professor Daniell’s,) in consequence of its affording a constant and regular current of electricity of very weak tension, con- tinuing for several weeks or even longer without any fresh addition of exciting fluid. A glass cylinder, T5 inch in diameter and 4 inches in length, was closed at one end by means of a plug of plaster of Paris 07 inch in thickness : this cylinder was fixed by means of corks inside a cylindrical glass vessel about 8 inches deep and 2 inches in diameter. A piece of sheet copper, 6 inches long and 3 inches wide, (having a copper conducting wire soldered to it,) was loosely coiled up, and placed in the small cylinder with the plaster bottom : a piece of sheet zinc of equal size was also loosely coiled up, and placed in the larger external cylinder (being furnished like the copper plate with a conducting wire). The larger cylindrical glass being then nearly filled with weak brine, and the smaller with a saturated solution of sulphate of copper, the two fluids being prevented from mixing by the plaster of Paris diaphragm, the apparatus is complete* ; and if care is taken that the fluids in the two cylinders are at the same level, will continue to afford a continuous current of electricity for some weeks, the sulphate of copper being very slowly decomposed. So feeble is the cur- rent evolved by an apparatus of this kind, that on connecting the two conducting wires with a common galvanometer, (having but one needle suspended on a pivot,) a deviation to only 10° or 12° took place: with Nobili’s galvanometer, with nearly astatic needles, a deviation to 90° immediately ensued, as might be expected from the greater delicacy of the instrument. So small, indeed, is the quantity of electri- city evolved by the apparatus I have described, as compared to that evolved by the ordinary electromotor, that I was unable to produce the simplest form of electro- magnetic rotation by its aid. After it has been in action for some weeks, chloride of zinc is found in the external cylinder, and beautiful crystals of metallic copper, fre- quently mixed with the ruby protoxide (closely resembling the native ruby copper ore) and large crystals of sulphate of soda, are found adhering to the copper plate in the smaller cylinder, especially on that part where it touches the plaster diaphragm. * So simple an apparatus scarcely requires an illustration : in the accompanying outline sketch I have, how- ever, figured it, to prevent any error arising from the account in the next not being sufficiently explicit. Fig 1. represents the battery connected with the apparatus described in paragraph 4. A. The external cylinder. B. The smaller one ; with D. The plaster of Paris bottom. C. The coil of copper in the cylinder B, having the conducting wire F soldered to it. E. The coil of zinc with the wire G soldered to it. 40 MR. BIRD ON THE ELECTRO-CHEMICAL INFLUENCE OF 5. If the two copper conducting- wires belonging to the little apparatus just described are immersed in water acidulated with sulphuric acid, action soon com- mences, bubbles of hydrogen appearing at the wire connected with the zinc plate, whilst that connected with the copper plate became tarnished, oxydized, and at last partly dissolved, giving a blueish tint to the fluid ; affording an approach to the de- composition of water by a single pair of plates. For the success of this experiment, it is, as might be expected, necessary that the positive electrode at least should be formed of a readily oxidizable metal ; for when both wires were of platinum, no evi- dence of decomposing action ensued. 6. If, instead of acidulated water, the wires were immersed into a solution of nitrate or acetate of lead, no immediate action ensued, but in about fifteen minutes, or even less, some elegant and delicate feathers of metallic lead, which rapidly in- creased in size, appeared at the negative electrode. This effect did not occur when both conducting wires were of platinum ; but when the negative electrode only was composed of that metal, the reduction of the lead continued with apparently increased energy. From these experiments, as well as many others of a similar kind which it is unnecessary to detail, it appears fair to presume, that in availing ourselves of the reducing agency of feeble currents, or at least of those elicited by a single pair of plates, it is necessary that the positive electrode should be composed of a readily oxidizable metal : thus using a kind of battery of two cells, in which the wires form- ing the electrodes, and the fluid submitted to experiment, form the contents of the second cell. 7- But few metallic solutions yield so readily as those of lead to the reducing agency of weak currents ; and where a longer time and continuance of action is required to effect the reduction, the decomposing apparatus of M. Becquerel will be found a useful addition to the little battery (4.), with the substitution of a plug of plaster of Paris for one of clay. This piece of apparatus is, in fact, a counterpart of the battery itself, consisting, like it, of two glass cylinders, one within the other, the smaller one having a bottom or floor of plaster of Paris fixed into it : this smaller tube may be about half an inch wide and three inches in length, and is intended to hold the me- tallic solution submitted to experiment, the external tube in which it is immersed being filled with a weak solution of common salt*. Into the latter solution a slip of amalgamated zinc, (for the positive electrode,) soldered to the wire coming from the copper plate of the battery (4.), is immersed, whilst for the negative electrode a slip of platina foil, fixed to the wire from the zinc plate of the battery, passes through a * Fig. 2. in the sketch represents this apparatus connected with the battery. A. The larger tube. B. The smaller one, with the plaster bottom. C. The electrode of amalgamated zinc connected by the wire F with the copper plate C of the battery (Fig. 1.). D. The negative electrode of platinum connected by the wire G with the zinc plate of the battery (Fig. 1.). LONG-CONTINUED ELECTRIC CURRENTS OF LOW TENSION. 41 «ork fixed in the mouth of the smaller tube, and dips into the metallic solution it contains. 8. When a solution of the chlorides or nitrates of iron, copper, tin, zinc, bismuth, antimony, lead, or silver, is placed in the smaller tube of the apparatus (7.), and con- nexion made with the battery* in the manner already described, action is almost instantly apparent, water is decomposed, and torrents of minute bubbles of hydrogen are evolved at the surface of the platinum plate, (negative electrode,) which continues for a short time, sometimes, indeed, lasting for hours ; a circumstance depending apparently upon the degree of facility with which the metal under experiment is reduced. Thus with solutions of copper, scarcely a bubble appears, the metal being almost immediately reduced, all the hydrogen being probably employed from the instant of completing the circle, for that purpose: with solutions of lead, tin, or silver, the evolution of hydrogen continues for a short time only, and ceases as soon as the minutest portion of reduced metal appears on the platinum plate ; but with solutions of iron and manganese the evolution of gas frequently continues for six, eight, or ten hours, or even longer ; the evolution of hydrogen thus seeming to bear something like an inverse ratio to the ease with which metal is reduced. After the hydrogen has ceased to appear at the negative electrode, striae of the reduced metal, which rapidly increase, are deposited on the surface of the platinum. 9. The metals thus reduced generally, but not invariably possess a perfectly me- tallic lustre, are always more or less crystalline, and often very beautifully so, af- fording a considerable contrast to the irregular soft spongy masses obtained from the same solutions by means of large batteries. The crystals of copper obtained by the process just detailed (8.), rival in hardness and malleability the finest specimens of native copper, which they much resemble in appearance. The crystallization of bis- muth, lead, and silver by these means, is very beautiful, that of the former metal being lamellar, of a lustre approaching to that of iron, but with the reddish tint pe- culiar to this metal. Silver may be thus obtained of a snowy and indeed dazzling whiteness, usually under the form of needles. 10. The metallic solutions hitherto mentioned as yielding to the action of the little battery are, as is well known, equally acted on by larger voltaic batteries, consisting of a considerable number of alternations, the metal being reduced in a spongy form, often destitute of a metallic appearance. But there are some metals which are de- posited from their solutions as oxides only, when acted on by currents from large batteries, and yet are deposited in a brilliant metallic form if submitted to the action of the currents from the little apparatus already described (4). Of these nickel is an example : a solution of its chloride or sulphate, when placed in the smaller tube of the decomposing apparatus (7.)> yielding after some hours a crust of metallic nickel on the negative electrode, often of a silvery lustre on the surface immediately * It may here be proper to remark, that by the word battery in the course of the following observations I always allude to the modification of Prof. Daniell’s battery described in § 4. MDCCCXXXVII. G 42 MR. BIRD ON THE ELECTRO-CHEMICAL INFLUENCE OF applied to the platinum, that portion of the crust more in contact with the fluid being generally black, and frequently covered with a layer of the hydrated and gelatinous green oxide. 11. Finding that by means of this apparatus I could command a weak but conti- nuous current capable of reducing even the more refractory metallic oxides, I was anxious to ascertain whether the current was sufficiently energetic to cause the re- duction of those oxides which (as silica) do not yield to powerful batteries, and which M. Becquerel obtained only alloyed with iron. 12. The solution of silicon used by M. Becquerel was prepared by dissolving gela- tinous silicic acid in hydrochloric acid of commerce, which always contains iron; this on being submitted to the action of a single pair of plates deposited an alloy of iron and silicon on the negative electrode. As this solution contains but a very small quantity of silicon, I substituted a solution of fluoride of silicon in alcohol obtained by passing a current of the gaseous fluoride into strong alcohol. On filling the smaller tube of the decomposing apparatus (7.) with this solution, and making the connexion with the battery in the manner already described, bubbles of hydrogen were copiously evolved at the surface of the platinum plate (negative electrode), which continued for eight or ten hours, when the platinum appeared to be tarnished, and in twenty-four hours a copious deposit of silicon had taken place on the platinum, to the surface of which it firmly adhered. Around the reduced silicon, and suspended in the fluid, was a dense gelatinous cloud of silicic acid. On quickly withdrawing the slip of platinum, dipping it in water, and then pressing it between folds of bibu- lous paper it was dried, and freed from any adhering solution. The silicon was nearly black and granular, under a lens, exhibiting a tendency to a crystalline form. It was not deposited on the platinum in a confused or irregular manner, but in lon- gitudinal striae, which appeared to follow the direction of certain lines of minute eminences on the surface of the piece of platinum, produced apparently by scouring it with fine sand and a piece of cork before being used for the construction of the negative electrode. 13. The silicon thus procured becomes of a snowy whiteness when ignited in the flame of a spirit lamp, and falls off the platinum in thin flakes, being in fact converted into silicic acid. It is not very easy to oxidate the whole, in consequence of the flakes of the acid forming an incrustation over the subjacent silicon, and protecting it from the oxidating influence of the air even at a red heat. A portion of the silicon re- movedl from the platinum did not appear to dissolve in hydrochloric acid ; but when the platinum itself with the firmly adhering silicon was immersed in the acid, slow action ensued, bubbles of hydrogen being evolved from the exposed surface of pla- tinum, the silicon very slowly disappearing ; the solution being probably occasioned by the formation of a simple voltaic circle, the silicon and platinum being the metals, and the acid the exciting fluid. When an aqueous solution of hydrofluosilicic acid is substituted for the fluoride of silicon, the metalloid is reduced, but slower and in LONG-CONTINUED ELECTRIC CURRENTS OF LOW TENSION. 43 smaller quantity ; differences arising in all probability from the smaller quantity of silicon present in the solution. 14. I have frequently had occasion to observe that when an aqueous solution of hydrofluosilicic acid has been submitted to the action of currents of low tension (from the battery already described (4.)) continued during two or three weeks, a consider- able deposition of gelatinous silicic acid takes place around the reduced silicon ; mixed with which, or precipitated in a zone on the sides of the tube, especially if of small diameter, or even upon the platinum electrode itself, frequently appear minute crystalline grains of sufficient hardness to scratch glass, and appearing translucent under the microscope. These minute crystals I have no hesitation in stating to be crystallized silicic acid, closely resembling its natural form of quartzose sand. 15. I next attempted to form potassium with the same apparatus, but failed, as I had anticipated, from the presence of water, which indeed would react on the potas- sium as soon as reduced. I therefore endeavoured to form its amalgam, well knowing that when dissolved in mercury a very weak electric current is sufficient to prevent the oxidating influence of water upon it ; and by using a modification of the decom- posing apparatus before described (/.) I succeeded perfectly. In place of the smaller tube containing the metallic solution, I used a small glass funnel*, the beak of which was carefully filled up with plaster of Paris : on this plaster floor I placed a piece of glass tube closed at one end, about 0‘5 inch in length and 0*2 inch in diameter, and half filled with pure mercury ; this tube was not placed vertically, but inclined so as to form an angle of about 40° with the plaster floor of the funnel, which with its contents was partly immersed in the weak brine contained in the larger cylinder of the decomposing apparatus. The external cylinder communicated as before with the copper plate of the battery, by means of a slip of amalgamated zinc dipping into the brine it contained. The funnel was then nearly filled with a solution of chloride of potassium, and a piece of platinum wire connected with the zinc plate of the battery being twisted into a flat spiral at one end so as to present a larger surface, was im- mersed in the mercury contained in the little tube submerged in the saline contents of the funnel. The circuit being thus completed, galvanic action soon became ap- parent, bubbles of hydrogen being evolved from the surface of the mercury (which now formed the negative electrode) in a very curious manner, not in confused and rapid streams, but in large and distinct bubbles, which very slowly appeared, and performed several gyratory movements on the surface of the fluid metal before they were evolved. Not unfrequently a single bubble only was seen, which continued * This variety of the apparatus is shown in fig. 3. of the outline sketch. A. The external vessel containing the salt and water. B. The funnel containing the alkaline salt required, with its plaster floor F. C. The positive electrode of amalgamated zinc communicating with the copper plate of the battery (fig. 1.). D. The little tube containing mercury immersed in the alkaline solution with a platinum wire E, connected with the zinc plate of the battery (fig. 1.) dipping into it. G 2 44 MR. BIRD ON THE ELECTRO-CHEMICAL INFLUENCE OF playing on the surface of the mercury for half an hour, or even longer, before it rose to the surface of the fluid. In about eight or ten hours the mercury had swollen to double its former bulk, and part of it had actually crept * up the platinum wire to the height of 0'3 inch above the level of the other portion, adhering to the wire like so much tenacious mucilage. On dipping a piece of turmeric paper into the contents of the funnel it turned brown, demonstrating the presence of an alkali. The mercury was removed from the little tube as quickly as possible, and poured into distilled water, which acted upon it, causing the evolution of hydrogen gas from its whole surface, and became alkaline from the formation and solution of the oxide of potas- sium or potass. The film of mercury adhering tothe platinum wire remained on it for some days, giving it the appearance of having been amalgamated. This experi- ment, several times repeated, yielded precisely similar results, from which I think that I am justified in stating that potassa can be reduced by means of the feeble current elicited by a single pair, or as the positive electrode was formed of an oxidi- zable metal, in the opinion of some, perhaps of two pairs of plates. 16. By submitting in the same apparatus a solution of chloride of sodium to the influence of the battery, analogous results were obtained. An amalgam of sodium being formed, although a much longer time was required, and the result of the ex- periment, although quite decided, Avas by no means so distinct as in the case of the reduction of potassium. 17- But of all the saline solutions that I have yet submitted to experiment, none afforded such conclusive and interesting results as those of ammonia. The ammo- nium being reduced with almost as much ease as copper or tin, when a solution of its chloride (hydrochlorate of ammonia) is submitted to the action of the voltaic cur- rent in contact Avith mercury, in the same manner as chloride of potassium or sodium. The same adhesion and creeping up of the mercury along the wire (15.) is observed, and after a few hours the fluid metal swells to five or six times its former bulk. On removing it quickly and drying it, by allowing it to fall on bibulous paper the amal- gam of ammonium is obtained of a buttery consistence, possessing a dull silvery colour, and yielding a peculiar crackling, or (if I may be allowed the expression) an emphysematous sensation to the finger on pressing it : on being immersed in water it very slowly gave off* hydrogen, and yielded a solution of ammonia. 18. By far the most satisfactory method of obtaining this amalgam is by using for the negative electrode a piece of platinum wire coiled up at one end, after it has been amalgamated by dipping it into the ammoniacal amalgam obtained by the last de- scribed process (17-)- A minute quantity of mercury is thus made to adhere to the wire, Avhich being connected with the zinc side of the battery, is dipped into a solu- tion of hydrochlorate of ammonia contained in the smaller tube of the apparatus used in effecting the reduction of silicon (7.). The circuit being completed, a few bubbles * This peculiar creeping up of the mercury along the wire does not take place if the little tube holding the fluid metal is placed in a vertical position. LONG-CONTINUED ELECTRIC CURRENTS OF LOW TENSION. 45 of hydrogen are disengaged from the amalgamated wire, which soon cease, and in an hour or two, a leaden grey spongy mass is observed adhering to the wire, which is sometimes sufficiently bulky to fill the tube, and putting on much of the external ap- pearance of a mass of cellular galena. This mass consists of a spongy amalgam of ammonium, containing a very minute proportion of mercury; it is lighter than the solution in which it is immersed, for on adroitly separating a portion of it, it rises to the surface and rapidly decomposes water, hydrogen being evolved and ammonia formed. 19. It is a very curious and interesting fact, that although this spongy ammoniacal amalgam cannot be kept immersed in water even for a few instants without the for- mation of ammonia, yet as long as it is connected with the negative electrode of the battery, it may be preserved without change for days and weeks. The instant the connexion with the battery is broken, a mass of this amalgam, as large as a walnut, appears to vanish in a few seconds, torrents of minute bubbles being given off, and a scarcely appreciable quantity of mercury being left on the wire. On again closing the connexion with the battery decomposition recommences, and the amalgam is re- produced. 20. From a review of the results of these experiments, we cannot help being struck with the very energetic power of electric currents of weak tension ; currents of suffi- cient energy to reduce to the metallic state oxides on which currents of higher ten- sion from large batteries are comparatively powerless. This fact, although pointed out by Becquerel and other philosophers, has (as far as I am aware) never been before shown to hold good in the reduction of the alkaline metals. Potassium and ammonium not having, I believe, been previously obtained by the weak current ema- nating from the chemical action of saline solutions on a single pair of plates ; and silicon, although obtained by Becquerel combined with iron, has not been procured before in a pure state by electric currents, at least by those of feeble tension *. In conclusion I may be permitted to observe, that in applying weak electric cur- rents to the reduction of metallic oxides, it is absolutely necessary that a continuous current be employed, and that its cessation even for an instant is of ten fatal to the suc- cess of the experiment on hand, which cessation or suspension, as far as my experi- ments have gone, the modification I have proposed of Professor Daniells battery appears to be capable of obviating. Guy s Hospital, January 20, 1837- * Some other curious circumstances connected with the decomposing electro-chemical power of currents of low tension have fallen under my observation, hut have not yet been sufficiently examined to authorize their publication as facts. Some of these I may perhaps at a future period, with the permission of the Society, have the honour of submitting to its notice. I l [ 47 ] VI. Inquiries respecting the Constitution of Salts. Of Oxalates , Nitrates , Phosphates , Sulphates, and Chlorides. By Thomas Graham, Esq. F.R.S. Edin., Professor of Chemistry in the Andersonian University of Glasgow, Corr. Member of the Royal Academy of Sciences of Berlin, 8$c. Communicated by Richard Phillips, Esq. F.R.S. Received June 23, — Read November 24, 1836. From the results obtained in a former paper upon water as a constituent of sul- phates, it seemed likely that a close analogy would generally be found to exist between any hydrated acid and the magnesian salt of that acid. The sulphate of water is constituted like the sulphate of magnesia ; and so do I now find the oxalate of water to resemble the oxalate of magnesia, and the nitrate of water to resemble the nitrate of magnesia. Indeed it appears probable that the correspondence between water and the magnesian class of oxides (as we may call the metallic oxides isomorphous with magnesia) extends beyond their character as bases, — that in certain subsalts of the magnesian class of oxides we have the metallic oxide replacing the water of crystallization of the neutral salt, or discharging a function which was thought pe- culiar to water. In the formation of a double sulphate a certain kind of substitution or displace- ment was observed, such as the displacement of an atom of water pertaining to the sulphate of magnesia, by an atom of sulphate of potash, to form the double sulphate of magnesia and potash. The same kind of displacement appears to occur likewise in the construction of double oxalates ; and the tracing of it enables us to form an idea of the constitution both of the double and of the superoxalates, and to explain their derivation, as in the case of the sulphates. I. Of the Oxalates. The oxalates promised ample scope for investigation from their number and variety. For we have not only neutral oxalates, double oxalates, and binoxalates, but likewise an unparalleled combination, the quadroxalate of potash, of which the true constitu- tion or proximate composition is a most interesting subject of inquiry. 1. Oxalate of Water, or Hydrated Oxalic Acid. H CC H2. The recent and accurate experiments of Berzelius, Gay-Lussac, and Turner, leave no doubt that the crystals of oxalic acid contain three atoms of water. I find I 48 PROFESSOR GRAHAM ON THE CONSTITUTION OF the acid to crystallize with this proportion of water in a variety of circumstances, and believe that it is never deposited from its aqueous solution in any other state. Of these three atoms of water one atom is basic, which is expressed in the formula by placing its symbol before that of the acid ; while the other two atoms of water are attached to this oxalate of water, and may be termed the constitutional water of the oxalate of water. These two atoms of water are found in the oxalate of magnesia, the oxalate of zinc, and the other oxalates of the magnesian class, as well as in the oxalate of water. It is well known that oxalic acid can likewise exist in combination with no more than one atom of water (its basic water), and is obtained in that state by drying it at a temperature a little above 212° Fahr., or on subliming the hydrated acid by a higher temperature. I have made many experiments in order to discover whether, in the case of the other two atoms of water, one is retained more strongly than the other, or whether an oxalate of water with one additional atom of water, instead of two, could be obtained. The common crystals were dried at various temperatures, both in air and in vacuo, but either none of the water was lost, or the entire two atomic proportions. There is certainly no intermediate hydrate. 2. Oxalate of Zinc. Zn CC H2. In the oxalate of water we observe a contracted solubility, and all the oxalates of the magnesian class of oxides are very sparingly soluble in water. They may be ob- tained by precipitation, on mixing a solution of oxalate of potash with sulphate of zinc, &c. Cold solutions of the salts were always made use of in our experiments ; and the precipitates, which were always granular and more or less distinctly crystalline, were washed with cold water, and dried by exposure to the air for a week or two, without the application of artificial heat. The oxalate of zinc is admitted to possess two atoms of water, and these I find are retained pretty strongly, as in the case of oxalate of water. It was observed that 24*95 grains of the salt lost only 0*44 grain by three days exposure to 212° Fahr. ; but by a few hours at 315° Fahr. the salt lost in all 4*87 grains of water, and appears to have become anhydrous. 3. Oxalate of Magnesia. Mg CC II2. The oxalate of magnesia retains its two atoms of constitutional water very strongly, and it is doubtful whether they can be expelled without decomposing the salt ; 1374 grains of the salt lost only 0*32 grain by an exposure to 212°, protracted for several days ; and by two days at 300° Fahr. the whole loss amounted only to 0’47 grain. 22*36 grains of the same salt, ignited, left 5*94 grains of caustic magnesia, or one part OXALATES, NITRATES, PHOSPHATES, SULPHATES, AND CHLORIDES. 49 of the salt contains (P2656 magnesia. A salt constituted with two atoms of water should contain CP2759 magnesia, of which the specimen analysed falls a little short, probably from containing some hygrometric moisture. The oxalate of manganese lost nothing at 212°, and was found by analysis to contain 0-2416 water, which approaches very closely the quantity equivalent to two atoms, namely, 02474 water in one hydrated oxalate of manganese. In regard to several other oxalates of this class, namely, the oxalate of the prot- oxide of iron, of oxide of nickel, of oxide of cobalt, and of oxide of copper, I believe it is impossible to obtain them in a state of sufficient purity for analysis. They appear to cany down with them portions of the precipitating salts ; and they alter mani- festly in appearance and composition during the progress of the washing, to which they must be submitted for the purpose of purification. In the case of oxalate of copper, which was examined most particularly, the results were so anomalous that no inference whatever could be drawn from them. It will appear, however, that a neutral oxalate of copper with two atoms of water can exist but in combination with oxalate of potash, or with oxalate of ammonia, as a double salt. None of the oxalates of the magnesian class of oxides is more soluble in oxalic acid than in water, and none of them combines with that acid to form a binoxalate. The crystals, which are obtained on mixing together solutions of binoxalate of potash and sulphate of magnesia, and which have been supposed to be a binoxalate of mag- nesia, are really a mixture of oxalate of magnesia and of quadroxalate of potash. Hence there is no combination of oxalate of magnesia with oxalate of water ; which illustrates the fact that bodies of the same class, such as these two oxalates are, have no disposition to enter into union and form a new compound. 4. Oxalate of Lime. Ca CC H2. The oxalate of lime contains two atoms of water, like the oxalate of magnesia, but parts with its water more freely than that salt. Thus 12’06 grains of the hydrated oxalate of lime were found to lose 1*6 grain of water at 212° Fahr. in the course of two days, T68 grain in three days, T84 grain in six days, and nothing more in nine days. The salt originally consisted of 100 oxalate of lime united to 27'85 water, of which last it has lost 19‘53 parts, and retained 8'32 at 212°. It is probable therefore that the constitution of hydrated oxalate of lime is the same as that of hydrated oxa- late of magnesia, that oxalate of lime forms only one definite hydrate, containing two atoms of water, but that it parts with the whole of its constitutional water at a mo- derate temperature. MDCCCXXXVII. H 50 PROFESSOR GRAHAM ON THE CONSTITUTION OF 5. Oxalate of Barytes. Ba CC H. This oxalate differs from all the preceding1, and contains only one atom of water. It was formed by digesting an excess of oxalic acid upon carbonate of barytes, and afterwards washing the resulting oxalate with cold water. 20,60 grains of the oxa- late, calcined by a low red heat, left 16*45 grains carbonate of barytes, equivalent to 12*77 barytes. Hence it follows that the oxalate consisted of Composition of Ba CC H. Barytes 100 100 Volatile matter .... 6! *32 59*08 161*32 159*08 Before being washed this oxalate had a sour taste, and the volatile portion of it amounted to 67*01 parts instead of 61*32; but it was evidently the neutral oxalate with a little free oxalic acid. It was not a binoxalate ; nor did such a salt present itself on digesting the neutral oxalate in oxalic acid, so that I am constrained to deny the existence of a binoxalate of barytes. Indeed it is scarcely a matter of doubt that no supersalt whatever exists of barytes, strontian, lime, or of the magnesian class of oxides. 6. Oxalate of Potash. K CC H. Oxalate of potash is known to crystallize from solution with one atom of water, and with no other proportion. The crystals speedily become white and opake at 212° Fahr., from the loss of water, but cannot, I believe, be made quite anhydrous at that temperature ; at least a portion of the salt, which had been exposed to 212° for four days, still retained water, consisting of 100 oxalate of potash and 3*4 water, which is rather less than a third of the water which the salt originally contained (10*8 parts). The oxalate of potash becomes quite anhydrous when dried at 300°. Of salt so dried 100 parts reabsorbed 10*63 water in a damp atmosphere with the greatest avidity. The oxalate of potash has therefore a certain attraction for a single atom of water, and this is an important feature of the salt. 7. Binoxalate of Potash. K CC + H CC H2. This salt has hitherto been supposed to contain only two, but it certainly contains three atoms of water. 21*37 grains of the salt, calcined by a full red heat, which is necessary for complete OXALATES, NITRATES, PHOSPHATES, SULPHATES, AND CHLORIDES. 51 decomposition, left 10' 14 grains of carbonate of potash. Allowing the potash an equivalent proportion of oxalic acid, the salt must consist by this experiment of Potash 32'23 Oxalic acid . . . 49'38 Water 18'39 100* The water almost coincides with three atoms, which would amount to 18'42 per cent, of the salt. In the formation of the binoxalate of potash, the constitutional atom of water of the neutral oxalate of potash appears to be displaced by an atom of hydrated oxalic acid ; so that the formula of binoxalate of potash represents anhydrous oxalate of potash, followed by oxalate of water with two atoms of water, as given above. The same principle of derivation applies most happily to that anomalous salt, the qua- droxalate of potash, 8. Quadroxalate of Potash. Analytic formula . . . K (CC)4 IT7. Rational formula . . . K CC + H CC -j- 2 (IT CC IT2). The formula of the preceding salt is terminated by two atoms of water : let us re- place them by two atoms of hydrated oxalic acid, and we have the quadroxalate of potash. We thus derive the quadroxalate from the binoxalate, in the same way that the binoxalate itself is derived from the oxalate. There can be no doubt, from the accurate analysis of Berzelius, that this salt contains seven atoms of water. He found 100 parts of the quadroxalate of potash to yield by ignition 27'225 carbonate of potash. In an experiment in which 1 7*3 grains of the salt were ignited by us, there resulted 4*7 carbonate of potash ; which is 27'11 carbonate of potash from 100 quadroxalate. Berzelius determined the water directly by igniting the salt with oxide of copper, and found it to amount to 24'8 per cent, of the salt. Calculated from our experiment, the water comes out 25'05 per cent., while the theory of seven atoms of water in the salt requires 24'72 per cent. 1Q'87 grains of this salt, dried by a nitre-bath, of which the temperature was 240°, lost eventually 1'46 grains; or 100 salt lost 13'43. Four atoms of water amount to 14T2 per cent, of the salt, to which the experimental result approximates sufficiently to prove that this salt parts readily with four of its seven atoms of water. These four atoms of water are evidently the constitutional water of the two atoms of hydrated oxalic acid, which the quadroxalate contains. When the salt is still more strongly heated, oxalic acid itself goes off, partly as a sublimate and partly in a decomposed state. 52 PROFESSOR GRAHAM ON THE CONSTITUTION OF 9. Oxalates of Ammonia. The oxalate and the binoxalate of ammonia agree exactly in composition with the corresponding salts of potash, the hypothetic oxide of ammonium being substituted for potash. It has been supposed that no quadroxalate of ammonia exists ; but this is a mistake. Such a salt is formed, on dissolving together equal weights of binoxa- late of ammonia and hydrated oxalic acid, and is analogous in form and composition to the quadroxalate of potash. 10. Oxalate of Soda. Na CC. This salt is perhaps the least soluble of the salts of soda, and presents itself as a granular precipitate on saturating carbonate of soda with oxalic acid. Of the oxa- late of soda dried in air without the application of heat, 23'44 grains left 18’52 car bonate of soda when strongly ignited, or 100 oxalate yield 70'01 carbonate of soda. Now 100 anhydrous oxalate of soda should yield 79'09 carbonate of soda. Hence the oxalate of soda is correctly stated to be anhydrous. It nevertheless combines with hydrated oxalic acid, and forms a binoxalate. In this compound we have simply the attachment of an atom of the oxalate of water, to the atom of oxalate of soda, without the displacement of an atom of water, as in the formation of the binoxalate of potash. Probably the absence of the atom of water in the oxalate of soda indi- cates an indifference on the part of this salt to enter into further combination. There is certainly a binoxalate of soda ; but this binoxalate cannot support the further attach- ment to it of two atoms of hydrated oxalic acid, and there is no quadroxalate of soda. 1 1 . Binoxalate of Soda. Na CC + H CC II2. This salt I find to resemble the binoxalate of potash, in containing three atoms of water. 22’ 11 grains, strongly ignited, left 8’05 grains fused carbonate of soda; or 100 binoxalate leave 40'67 carbonate of soda, equivalent to 23*84 soda; while a bin- oxalate with three atoms of water should yield 23*95 per cent, soda, or almost exactly the experimental result. The binoxalate of soda lost little more than 1 per cent, of its weight when kept at 212° Fahr. over sulphuric acid in vacuo. But by a heat approaching 300° Fahr. the salt lost 14*64 per cent, of water, which is a little more than two atomic proportions, namely, 13*78 per cent. Hence this salt retains the whole of its constitutional water at 212°, but loses two atoms of it at a higher tem- perature, retaining strongly the third atom of water, which is basic. Double Oxalates. The number of double oxalates is not so great as is generally supposed. On mixing a solution of binoxalate of potash either with the muriate or the sulphate of magnesia. OXALATES, NITRATES, PHOSPHATES, SULPHATES, AND CHLORIDES. 53 zinc, &c., the oxalate of magnesia or of zinc precipitates, while the quadroxalate of potash is formed, and remains in solution or crystallizes, being very sparingly soluble, according to circumstances. When binoxalate of potash is digested upon magnesia or upon oxide of zinc, a portion of the oxide is dissolved, but is quickly deposited again as an insoluble oxalate, and no double salt formed. But one member at least of the magnesian class of oxides, namely, oxide of copper, is dissolved by the binoxa- lates of the alkalies, and forms double salts, which were discovered and carefully examined by M. Vogel of Bayreuth. 12. Oxalate of Copper and Potash. KCC + CuCCH2; and also KCC + CuCCH2 + H2. The binoxalate of potash, when considerably diluted, and digested with heat upon the oxide of copper, dissolves it easily, and a double salt of sparing solubility crystal- lizes, presenting itself generally in two forms, one of which contains two and the other four atoms of water, according to the analyses of M. Vogel, which I have repeated and confirmed so far as the water is concerned. The crystals containing four atoms of water soon become opake by exposure to the air, and lose two atoms of water by efflorescence. Binoxalate of ammonia likewise dissolves oxide of copper, and does so still more readily than the binoxalate of potash, which may depend upon the circumstance that the resulting double salt of ammonia is considerably more soluble in water than the double salt of potash. The oxalate of copper and ammonia crystallized in plates of a blue colour, and seemed to affect one form only. Of these plates, 9'38 grains were readily decomposed by heat, and left 2-37 grains black oxide of copper, or 25 27 per cent., which is almost exactly the proportion of that of the oxide of copper, which a salt of two atoms water should contain, namely, 25-37 per cent. This salt loses water readily at 212° Fahr. ; and of the 11'52 per cent, which it is supposed to have on the theory of its containing two atoms of water, 1T46 per cent, escaped by the exposure of the salt to that temperature. M. Vogel describes two other double oxalates of copper and ammonia; but it is evident that they contain ammonia and not oxide of ammonium ; so that they do not come under our consideration at present. It is to be remarked that the oxalate of copper and potash is represented above by a formula quite analogous to that of binoxalate of potash, oxide of copper being simply substituted for basic water. We have oxalate of potash in both cases, to which there is attached oxalate of copper with two atoms of water in the one formula, and oxalate of water with two atoms of water in the other. It is to be remembered that in the case of the sulphates, the double sulphate of copper and potash was shown to have a similar analogy in constitution to the bisulphate of potash. 54 PROFESSOR GRAHAM ON THE CONSTITUTION OF Oxalate of Chromium and Potash , of Peroxide of Iron and Potash, of Peroxide of Iron and Soda, 8$c. Cr'Cr CC3 + 3 K CC + H6. Fe Fe CC3 + 3 K CC + H6. Fe Fe CC3 + 3 Na CC + H10. This group of salts has not hitherto been submitted to analysis, although they occupy the same important position among the oxalates which the alums do among the sulphates. 13. Oxalate of Chromium and Potash. This remarkable salt was first described by Dr. Gregory, and its optical properties have been made the subject of a memoir by Sir David Brewster*. It is easily pre- pared by the following process, which is Dr. Gregory’s, with the proportions slightly altered, from a knowledge of the composition of the salt. One part of bichromate of potash, two parts binoxolafe of potash, and two parts hydrated oxalic acid, are dissolved together in hot water. There is a copious evolution of carbonic acid gas, arising from the deoxidation of the chromic acid, and nothing fixed remains except the salt in question ; of which a pretty concentrated solution crystallizes upon cooling in prismatic crystals, which are black by reflected light, but of a splendid blue colour by transmitted light, when sufficiently thin to be translucent. This salt, strongly dried without decomposition, was found to lose 1F67 per cent, of water. The oxide of chromium cannot be precipitated from it completely by means of an alkaline carbonate, and it is very remarkable that only a small portion of the oxalic acid is thrown down from this salt by chloride of calcium. To determine the proportion of oxalic acid, the salt was heated in strong sulphuric acid, and the gases allowed to escape through a tube containing chloride of calcium. 15T9 grains of the crystals lost 6*71 grains by this treatment, which loss is the weight of the oxalic acid. Hence this salt contains 44-17 per cent, of oxalic acid. When this double oxalate is ignited, carbonic oxide escapes, and the residuary salt is a mixture of chromate and carbonate of potash, which is entirely soluble in water, and contains no oxide of chromium. In four experiments the fused residuary salt amounted to 0'5458, 0-5411, 0'5454, and 0"5425 of the weight of the crystals operated upon, while it should be 0"5433, provided this residuary salt is a mixture of two atoms chromate and one atom carbonate of potash, and that the composition of the crystals is as follows : * Philosophical Transactions, 1835. OXALATES, NITRATES, PHOSPHATES, SULPHATES, AND CHLORIDES. 55 One atom oxide of chromium, CrCr . . . 1003*6 16*28 Three atoms potash, 3 K 1769*7 28*70 Six atoms oxalic acid, 6 CC 27 1 7*4 44*07 Six atoms water, 6 H 675* 10*95 6165*7 100* The results in regard to the water and oxalic acid narrated above, agree completely with this view, and so does the determination of the oxide of chromium. 26*01 grains of the crystals left, when ignited, 14*08 grains of the mixed chromate and carbonate of potash, which were dissolved in water, and being acidulated with acetic acid, the chromic acid was precipitated by acetate of lead, and gave 17*45 grains chromate of lead, equivalent to 4*28 grains oxide of chromium. Hence by this experiment the crystals contain 16*46 per cent, of oxide of chromium, which approaches very nearly to the theoretical result. The fused residuary chromate and carbonate of potash amounted to 0*5425 of the weight of the crystals, which is so near the theoretical result, namely, 0*5433, that we may safely conclude that the quantity of potash in the salt agrees with our theoretical estimate. This salt is clearly, therefore, a compound of one atom oxalate of chromium, con- taining three atoms oxygen in the oxide and nine atoms oxygen in the acid, with three atoms oxalate of potash; and the salt has six atoms of water of crystallization. The oxygen in the oxide of chromium being 1, that in the potash is also 1, that in the water 2, and that in the oxalic acid 6. I made several attempts to crystallize the oxalate of chromium itself, but without success, so that I had no opportunity of studying its constitution in relation to the constitution of the preceding double salt. 14. Oxalate of Peroxide of Iron and Potash. This salt, which has not hitherto been described, is formed by dissolving the hydrated peroxide of iron to saturation in binoxalate of potash. There is no effer- vescence, but a sap-green solution results, which, when concentrated, deposits the salt in question in tabular crystals, of which the form has no resemblance to that of the corresponding oxalate of chromium and potash, and which are of a beautiful grass-green colour. These crystals are permanent in the air, unless it is very dry, when they lose water by efflorescence and become brown and opake. The solution of the salt is decomposed by ammonia, and the peroxide of iron completely thrown down. The salt, when ignited, leaves peroxide of iron and carbonate of potash. It loses 10*56 per cent, of water at a temperature not exceeding 230° Fahr., but is par- tially decomposed at 300°. Below, the theoretical composition of this salt is placed in juxtaposition with the results of an analysis. 56 PROFESSOR GRAHAM ON THE CONSTITUTION OF Theory. Experiment. One atom peroxide of iron . . 1593 16-13 Three atoms potash .... . . 28-82 29-07 Six atoms oxalic acid . . . . . 44-25 43-74 Six atoms water ..... . . 11-00 10-56 100- 99-50 Hence its composition is the same as that of the preceding salt. iron being substituted for chromium. 15. Oxalate of Peroxide of Iron and Soda. This salt is formed by dissolving the hydrated peroxide of iron in binoxalate of soda. It crystallizes in solid green crystals. It is composed as follows, the water being calculated from the loss on the analysis : Theory. Experiment. One atom peroxide of iron . . 16-32 16-56 Three atoms soda . . 19-57 19-66 Six atoms oxalic acid . . . . . 45-34 45-51 Ten atoms water ..... • . 18-77 18-27 100- 100- Of the ten atoms water which this salt contains it readily loses six at 212° Fahr., and retains four atoms wafer at that temperature. It differs, therefore, in composi- tion, and it does so also in form, from either of the preceding double oxalates. A corresponding oxalate of chromium and soda was produced by a similar process, and crystallized with some difficulty in solid dark crystals, which appeared to have the same form as the preceding soda-salt, and were found, like it, to contain ten atoms of water. There is also a double oxalate of alumina and potash, which may be made by dis- solving hydrated alumina in binoxalate of potash, and crystallizes in white tables of a pearly lustre, which have the same form as the oxalate of iron and potash. II. Of Nitrates. 1. Hydrated Nitric Acid, the Nitrate of Water. H N li3. Nitric acid combines with one atom of water as base, and with three atoms more by a less powerful affinity. The well-defined character of the combination containing four atoms water, which is the acid of specific gravity 1*42, is evinced in its high boiling point and in an appearance of saturation which it exhibits. The true and complete nitrate of water has therefore three atoms of constitutional water attached to it. And in the case of the nitrates of those metallic oxides which correspond with OXALATES, NITRATES, PHOSPHATES, SULPHATES, AND CHLORIDES. 57 water in their basic character, we find the water of crystallization likewise to be three atoms, or a multiple of three, and no other number. 2. Nitrate of Copper. C'UNH3; and also C u N H3 -f 3 H. There are two nitrates of copper, one of which crystallizes in prisms, and the other in rhomboidal plates of a lighter blue colour than the prisms ; the first of which I find to contain three and the other six atoms of water. Both are deliquescent to a certain degree, the salt which contains the large proportion of water being more so than the other. (1.) Of the dark blue prisms, 28-12 grains carefully calcined left 8-98 grains black oxide, or 3T94 per cent. In a second experiment, 22 '9 grains left 7‘34 grains oxide, or 32-05 per cent. The salt being neutral in composition, the quantity of nitric acid may be inferred from the oxide of copper, and the difference between their sum and the weight of the salt operated upon is the water. By the first analysis the water amounts to 3-38, and by the second to 3-28 atomic proportions. The excess above three atoms is probably hygrometric moisture, to remove which from this salt we cannot employ the ordinary means. In a third experiment upon a portion of the same salt, which had been dried over sulphuric acid till it began to effloresce, 33-19 grains of nitrate left 1T04 grains oxide, which gives 2-83 atomic proportions of water to the salt, or the result is a little below the three atoms. Hence this nitrate may safely be supposed to possess three atoms of water. (2.) Of the lighter coloured crystals in plates, 10-60 grains left 2‘78 grains oxide of copper when ignited, or 27'36 per cent. Hence the salt is composed of With six atoms water. Nitrate of copper . . . 6-57 100- 100- Water . . 4-03 6T33 57’54 10-6 16T33 157-54 The experimental determination is a little above the theoretical estimate, as might be expected from the deliquescent nature of the salt. The crystals speedily became opake over sulphuric acid in vacuo, and 10-6 grains lost 2*18 grains water in a night, retaining T85 water; which is 28"16 water retained to 100 anhydrous salt, or almost exactly three atoms of water. Hence this salt parts easily with half its water. The other three atoms of water are retained more strongly; for by a second day’s exposure over sulphuric acid there was an additional loss of only 0-15 grain water ; or the water retained was reduced to 25‘87 parts united to 100 anhydrous salt. MDCCCXXXVII. I 58 PROFESSOR GRAHAM ON THE CONSTITUTION OF 3. Subnitrate of Copper. HNCu3. It is well known that when the nitrate of copper is heated to the temperature of 400° or 500° Fahr., it is decomposed, nitric acid and water being expelled, and a sub- nitrate remaining, which consists of one atom of nitric acid, one atom of water, and three atoms of oxide of copper. This decomposition I find to take place and be com- pleted at a very moderate temperature, not exceeding 150° Fahr. ; and it appears, be- sides, that none of the three constitutional atoms of water of the nitrate of copper can be expelled without a certain corresponding loss of acid : that on heating the salt in question, nitric acid and water go off together, in the form of nitrate of water with its three atoms water. Thus, three atoms of crystallized nitrate of copper, containing three atoms acid, three atoms oxide, and nine atoms of water, are resolved into two atoms nitrate of water, each containing one atom acid and four water ; and one atom of subnitrate of copper, which contains one atom acid, one water, and three oxide of copper. Experiment. — In a stove of which the temperature never exceeded 150° Fahr., 27'54 grains crystallized nitrate of copper, containing three atoms of water, exposed on a capsule, suffered the following gradual reduction of weight : a loss of 2*59 grains in one day, of 9*62 in six days, of 1 IT in seven days, of 13*35 in eleven days, of 13*47 in twelve days, of 13*58 in sixteen days, of 13*60 in eighteen days, and nothing more afterwards by a heat of 300° Fahr., continued for several hours. Of the crystallized nitrate, 27'54 grains have left 13*94 grains subnitrate; or we have 0*5062 subnitrate from 1 nitrate. By calculation the residuary subnitrate should be 0*5026, with which the experimental result closely corresponds. Another portion of the same nitrate of copper, dried exactly in the same way, lost 1 per cent, of its weight when afterwards heated to 400° Fahr. ; and thereafter, being- ignited, was found to consist of Experiment. Theory. Oxide of copper .... 100* 100* Volatile matter .... 53*19 53*1 153*19 153T I am satisfied that no other subnitrate except the preceding, which contains three atoms of oxide of copper, can be obtained by the decomposition of the neutral nitrate by means of heat. For a quantity of the subnitrate of copper of the first experiment narrated above being gradually exposed in a platinum crucible to a heat above the melting point of lead, by means of a sand-bath, so as actually to reduce a portion of the subsalt in contact with the bottom of the crucible to the state of black oxide, yet the major portion of the subsalt, which still retained its green colour, was found to be little altered in composition. After this extreme heating the subsalt consisted of OXALATES, NITRATES, PHOSPHATES, SULPHATES, AND CHLORIDES. 59 Oxide of copper . . 100’ Volatile matter . . 506 ]506 Or the proportion of volatile matter in the subsait has suffered only a small reduc- tion, namely, from 53- 1 to 50-6 parts. This last subnitrate afforded drops of nitric acid with fumes of nitrous acid when heated in a tube, so that the subnitrate of cop- per retains water even at a temperature above the melting point of lead. The subnitrate of copper merits a careful consideration ; for the subsalts of the magnesian class of oxides, which can be had of a definite composition, are really much fewer in number than is generally supposed. What constitution ought to be assigned to this salt ? It will be observed that I have represented it by the singular formula HNCu3; implying that the single atom of water which it contains is really the base of the salt, and that the three atoms of oxide of copper are in the place of the constitutional water of this nitrate of water. This opens a new view of the constitution of subsalts. The excess of metallic oxide which they contain may not be basic at all in certain cases like the present, but discharge a function in the constitution of the salt which has hitherto been recognised only as executed by water. For if we find water and oxide of copper strongly resembling each other as bases, why may not the analogy between them extend further, and oxide of copper be capable of discharging the function of constitutional water or water of crystallization in the composition of a salt ? Indeed the speculation that all salts whatever are neutral in composition is highly probable. Where the metallic oxide is in excess, as in what are called sub- salts, we can attribute another function than that of base to the whole or a portion of the metallic oxide, and thus preserve the salt neutral in composition, or according to its formula. To this subject I shall again recur. The following observation is particularly favourable to the view which we are taking of the constitution of subnitrate of copper. When the black oxide of copper is drenched with the strongest nitric acid, it is a subnitrate of copper which is formed, although the nitric acid may be in great excess. The black oxide is converted into a green powder, from which the excess of nitric acid should be drained off as well as possible, and the powder will be found to be in great part insoluble in water. The explanation seems to be, that the concentrated nitric acid employed does not contain the constitutional water which the neutral nitrate of copper requires, and accordingly that salt is not formed ; but the nitrate of water supplies itself with oxide of copper in the place of its deficient constitutional water ; so that the result is a nitrate of water with three atoms of oxide of copper attached. But when nitric acid of a spe- cific gravity not exceeding T42 is digested upon the same black oxide of copper, Ihe neutral nitrate of copper only is formed, and no subnitrate. 60 PROFESSOR GRAHAM ON THE CONSTITUTION OF This view seems likewise to be necessary to account for the great force with which the single atom of water is retained by the subnitrate of copper. The water cannot be expelled without decomposing the salt, notwithstanding the great excess of oxide of copper present. 4. Nitrate and Subnitrate of Bismuth. BiN Hs H N Bi3 The neutral nitrate is admitted to contain three atoms of water, like the nitrate of copper, and its constitution appears to be similar. No portion of the constitutional water of this salt can be expelled without decom- posing the salt. Indeed this salt loses acid by exposure to dry air at a temperature not exceeding 80° Fahr. The crystals of the salt are resolved by a heat of 212° into a solid and fluid portion, the first of which is probably the subnitrate, while the last is hydrated nitric acid containing much nitrate of bismuth in solution, and not a supernitrate of bismuth. But the fluid portion fixes so readily upon cooling that the solid product cannot be obtained in a definite state. Experiment. 28*63 grains of nitrate of bismuth in good crystals, being exposed to a gradual ignition, left 14T6 grains of fused oxide of bismuth. This result accords with the view which is taken above of the composition of this salt : Experiment. Theory, Oxide of bismuth ..... 14T6 100* 100* Nitric acid and water . . . 14*45 102*04 102*72 28*61 202*04 202*72 It appears likewise that three atoms of the hydrated nitrate of bismuth are re- solved, when dried at a high temperature, into two atoms hydrated nitrate of water and one atom subnitrate of bismuth, which last is of the same constitution as the subnitrate of copper. Experiment 1. Dried on the sand bath at a temperature above the melting point of tin, 28*61 grains of nitrate of bismuth lost 9*29 grains, and retained 5*16 grains of volatile matter, or consisted of Experiment. Subnitrate by theory. Oxide of bismuth. .... 14*16 100* 100* Volatile matter ..... 5*16 36*44 34*24 19*32 136*44 134*24 Experiment 2. A portion of nitrate dried in a stove at a temperature not exceeding 180° Fahr., till it ceased to lose weight, was thereafter found to consist of Oxide of bismuth 21*24 100* Volatile matter „ 7'57 35*64 28*81 135*64 OXALATES, NITRATES, PHOSPHATES, SULPHATES, AND CHLORIDES. 61 It appears from the second of these experiments that the subnitrate of bismuth may be produced at a temperature so low as 180° Fahr., and from the first experi- ment that the subnitrate may be exposed to a temperature of 500° Fahr. without de- composition. Several experiments were made to produce another definite subnitrate, containing a greater proportion of oxide of bismuth, by the action of heat upon this subnitrate, but without success. The salt was partially decomposed at various temperatures under redness, but no definite compound resulted. Hence the subnitrate described is probably the only definite subnitrate of bismuth that can exist. The small pearly crystals obtained on throwing the neutral nitrate of bismuth into a moderate quan- tity of water, are of the same composition as the subnitrate obtained by heat. 5. Nitrate of Zinc. Zn N H3 + 3 H. This salt is easily obtained by dissolving zinc in nitric acid. It is very soluble in water, and moderately deliquescent. Experiment. 29* 1 7 grains of the crystals ignited, left 7'86 grains oxide of zinc. In this experiment we have 0-2694 oxide from one salt, which is very near 0-2713 oxide, the proportion which should be left, supposing the salt to contain six atoms of water. By efflorescence at 212° one part of this salt loses 0-18 water, which is one half of the whole water which the salt is assumed to contain, namely, 0‘3639 water. It loses no acid at 212°. Hence tills salt is of the same constitution as the nitrate of copper, but is not decomposed at so low a temperature. The proportion of water, however, cannot be reduced below three atoms without a loss of acid, and there appears to be a subnitrate of zinc resembling the subnitrate of copper. 6. Nitrate of Magnesia. MgN H3 + 3 H. Experiment. 27' 12 grains of crystals of nitrate of magnesia, when calcined, left 4*3 grains caustic magnesia; a result which indicates 6-17 atomic proportions of water in the salt, or the salt contains six atoms of water. The nitrate of magnesia stands exposure to a heat which would melt lead without losing acid. At that high temperature the proportion of water is reduced to one atom, which cannot be expelled without loss of acid. The salt remains in a fused state and transparent, and dissolves afterwards completely in water. Experiment. 18-40 grains of the crystals, containing- 7*7 1 grains water, lost 6’60 grains by a strong sand-bath heat continued till the salt ceased to lose weight. This is a loss of exactly five sixths of the water contained in the salt. Experiment. 1976 grains, containing 8*28 water, by similar treatment lost 677, 62 PROFESSOR GRAHAM ON THE CONSTITUTION OF which approaches very closely to 6*90 grains, the number representing five atomic proportions of water. This single atom of water retained by the nitrate of magnesia, is not displaced and expelled upon heating the salt, together with an atomic proportion of nitrate of potash to 600° or 700° Fahr., so that the retention of an atom of water does not indicate a disposition, upon the part of nitrate of magnesia, to form a double salt. It is pro- bable that this peculiar and intimate combination of nitrate of magnesia with one atom water does not exist in the crystals or ordinary hydrate of nitrate of magnesia, but is the result of a new arrangement of the constituents of the salt at a high tem- perature. There are indications of the existence of a similar nitrate of water. There does not appear to be a subnitrate of magnesia like the subnitrate of copper. Supposed Double Nitrates and Supernitrates. As double nitrates are said to exist, I have repeatedly attempted to form them ; but when nitrate of magnesia, nitrate of zinc, or nitrate of copper was mixed with nitrate of potash or with nitrate of ammonia, the salts uniformly separated again in crystallizing. There is no proof of the existence of a single supernitrate. Most of the nitrates of oxides not belonging to the magnesian class are anhydrous salts, such as the nitrates of potash, soda, barytes, strontian, lead, &e., and do not suggest any new subject matter of inquiry. III. Of Phosphates. In the present state of our knowledge phosphoric acid is quite peculiar in being capable of combining with bases in three different proportions, forming, besides the usual class of salts containing one atom of acid to one atom of protoxide as base, two other anormal classes of salts, in which two and three atoms of base are united to one atom of acid, namely, the pyrophosphates and the common phosphates. Arsenic acid forms only one class of salts, but that class is anormal, every member of it con- taining three atoms of base to one atom of acid, like the common phosphates. These anormal classes of phosphates and arseniates, with perhaps the phosphites, are, I be- lieve, the only known salts to which the ordinary idea of a subsalt is truly applicable; or in the formulae of these salts only, ought more than one atom of any protoxide to appear in a basic relation to one atom of acid. All other reputed subsalts are pro- bably neutral in composition, as I have endeavoured to show in the case of the sub- nitrate of copper ; for to this salt they all bear an analogy in their small solubility and other properties, while they exhibit little resemblance to those classes of phos- phates and arseniates which really possess more than one atom of base. The fol- lowing Table contains the formulse of the most important phosphates, with a new nomenclature of these salts, which I offer for consideration. OXALATES, NITRATES, PHOSPHATES, SULPHATES, AND CHLORIDES. G3 First Class. Monobasic phosphate of water (metaphosphate of water) H P. Monobasic phosphate of soda (metaphosphate of soda) NaP. Second Class. Bibasic phosphate of water (pyrophosphate of water) . IT2 P. Bibasic phosphate of soda and water (bipyrophosphate of soda) Na II P. Bibasic phosphate of soda (pyrophosphate of soda) . . Na2P -f- 10 H. Third Class. Tribasic phosphate of water (common phosphate of water) H3 P. Tribasic phosphate of water and soda (biphosphate of soda) . NaH2P + 2lT. Tribasic phosphate of soda and water (phosphate of soda) Na2 H P + 24 H. Tribasic phosphate of soda (subphosphate of soda) . . Na3P + 24 II. Tribasic phosphate of soda, ammonia, and water (micro- cosmic salt) Na NH4 IT P T- 8 H. Tribasic phosphate of magnesia and water (phosphate of magnesia) . Mg2 H P + 2 H + 12 H. Tribasic phosphate of magnesia and ammonia (ammo- niaco-magnesian phosphate) Mg2 NIT4 P + 2 H + 10 H. It is my object to get rid of the trivial names pyrophosphates, metaphosphates, and common phosphates, which have tended to keep up an erroneous impression that the phosphoric acid is of a different nature in these classes of salts, or is modified in some way unknown. This notion has arisen from the pertinacity with which phosphoric acid continues combined with a constant number of atoms of base, whether it be one, two, or three, although the base itself be repeatedly changed by decomposing the original combination. But this is an occurrence quite analogous to the formation of different sets of sulphurets or of chlorides, when we decompose two or more different oxides of the same metal, such as the oxide and suboxide of mercury, by sulphuretted hydrogen or by muriatic acid. The metal continues in the same relative state of sa- turation throughout a series of such decompositions ; and so does the phosphoric acid, because in both cases the decomposition is effected by an equivalent substitution. A difficulty occurs in naming two members of the tribasic class, so as to distinguish them from each other, namely, the biphosphate of soda and phosphate of soda, both of which contain soda and water as base. But this difficulty is obviated by placing 64 PROFESSOR GRAHAM ON THE CONSTITUTION OF first in the name that base of which two atoms are present. Thus the bi phosphate of soda is “ the phosphate of water and soda,” and the phosphate of soda is the phos- phate of soda and water, both being- at the same time characterized as “ tribasic.” What I have to add at present in regard to the phosphates relates chiefly to the last three salts, of which formulae are given in the preceding Table, which belong to classes of tribasic phosphates that were not examined in my former paper upon the phosphates*. But I may premise a few observations, which are more strictly supple- mentary to the results of that paper. 1 . The bibasic phosphate of water (pyrophosphate of water) is possessed of very considerable stability. Both weak and concentrated solutions of this salt have been kept for five or six months without any sensible change or production of the tribasic phosphate of water. 2. It appears to be impossible to crystallize any bibasic phosphate (pyrophosphate) of potash. Such salts can exist in solution, but not in the dry state. The same ob- servation applies to the bibasic phosphates of ammonia, or we have no pyrophosphates of ammonia except in solution. Indeed, the solution of the bibasic phosphate of water and ammonia assumes another atom of basic water when the evaporation is carried far, and crystallizes as the tribasic phosphate of water and ammonia (biphosphate of ammonia). 3. In the case of tribasic phosphates containing potash, I have succeeded in cry- stallizing the tribasic phosphate of potash, and the tribasic phosphate of water and potash, but not the tribasic phosphate of potash and water, or what would be con- sidered on the old view as the neutral phosphate of potash. 4. Both the bibasic and tribasic phosphates of water maybe treated with an excess of caustic potash in solution without the formation of any precipitate or sparingly soluble combination. It is only in the monobasic phosphate of water that a sparingly soluble combination is formed by potash, such as that which is described by Dr. Thomson under the name of diphosphate of potash. I. Tribasic Phosphate of Soda, Ammonia, and Water. {Phosphate of Soda and Am- monia : Microcosmic Salt.) NaNHI. * * 4 H P + 8 H. I have repeated more than once the analysis of this salt, and obtained the same result as M. Mitscherlich. It appeared to contain 0-5094 of volatile matter: and there may be derived from an atom of this salt one atom of phosphoric acid, of soda and of ammonia respectively, and ten atoms of water. It has hitherto been viewed as a double phosphate or combination of phosphate of soda with phosphate of am- monia ; but no reason can be assigned why these particular salts should combine together, and combinations of salts of soda and ammonia are exceedingly unusual. * Philosophical Transactions, 1833. OXALATES, NITRATES, PHOSPHATES, SULPHATES, AND CHLORIDES. 65 The view expressed above in the formula is much more likely to be true, namely, that this salt is simply a tribasic phosphate, of which the three atoms of base are all dif- ferent : they are soda, oxide of ammonium, and water ; and the salt possesses eight atoms of water of crystallization. By a graduated heat it is possible to expel the water of crystallization of this salt, and likewise the ammonia of its oxide of ammo- nium ; and the water of the last remaining as base, the salt Na H2 P is produced. M. Mitscherlich now admits that there is no tribasic phosphate corresponding with this, but containing potash instead of oxide of ammonium, a conclusion of which I have ascertained the accuracy. I endeavoured to form a tribasic phosphate to contain two atoms soda and one atom of oxide of ammonium, but such a salt appears to have no existence. For when ammoniacal gas was passed into a strong and hot solution of the common phosphate of soda, a slight deposition of the tribasic phosphate of soda took place, followed by the rhomboid.al crystals of the common phosphate unchanged. It likewise appears that when the bibasic phosphate of soda and the bi basic phos- phate of potash (pyrophosphates) are mixed together, no new salt is produced ; but the former may be crystallized out, and the latter remains uncrystallizable. II. Tribasic Phosphates containing Oxides of the Magnesian Class . 1. Tribasic Phosphate of Zinc and Water. ( Phosphate of Zinc.) Zn2 H P + 2 H. This salt, which is nearly insoluble, is obtained in minute silvery plates, by mixing three ounces of sulphate of magnesia with four ounces of phosphate of soda, each dissolved in two pounds of cold water. These crystalline plates consist of Theory of Zn H P + 2 H. Anhydrous salt . . . 100” 100* Water ..... 19-63 17*77 119-63 117-77 Dried above the melting point of tin the crystals still retained a glistening appear- ance, but had lost two thirds of their water ; for they now consisted of Theory of Zn H P. Anhydrous salt . . . 100- 100- Water ..... 6-08 5-92 106-08 105-92 The two atoms of water which are expelled in the above experiment are, notwith- standing, pretty strongly attached to the salt, being retained at the boiling point of water. Indeed these two atoms of water are highly constitutional, and are found in all the phosphates of this class. mdcccxxxvii. k 66 PROFESSOR GRAHAM ON THE CONSTITUTION OF This phosphate fuses at a red heat, after it becomes anhydrous, but it continues soluble in dilute acids. 2. Tribasic Arseniate of Magnesia and Water. ( Arseniate of Magnesia.) Mg-2 H As + 2 H -f 12 H. This salt precipitated on mixing- dilute solutions of 500 grains of arseniate of soda and 300 grains of sulphate of magnesia. It consisted of Theory of Mg2 H As + 14 H. Anhydrous salt . . . 100‘ 100- Water 86-53 86-25 186-58 186-25 This salt contains in all fifteen atoms of water, of which three are retained and twelve expelled at the boiling point of water. Dried at 212° it consisted of Theory of Mg2 H As -f 2 H. Anhydrous salt . . . 100- 100- Water ..... 17-17 17-25 117-17 11725 It therefore retains pretty strongly two atoms of water besides its basic atom, resem- bling the preceding salt in this respect. This arseniate and the corresponding phosphate are rendered insoluble in dilute acids by the effect of a strong red heat. 3. Tribasic Phosphate of Magnesia and Water. {Phosphate of Magnesia.) Mg2 HP + 2H + 12 H. This salt appears in distinct prismatic crystals in the course of twenty-four hours, upon mixing two ounces of sulphate of magnesia with three ounces phosphate of soda, each dissolved in two pounds of water. Cold water is capable of dissolving about one thousandth part of its weight of these crystals. They have been stated erro- neously to be much more soluble. The proportion of water which they contain has hitherto been stated at fourteen atoms instead of fifteen, which is the truth. By ana- lysis the crystals were found to consist of Theory of Mg2 H P + 14 H. Anhydrous salt . . . 100' 100- Water 121-7 119-76 221-7 219-76 I find that the proportion of water retained by this salt is readily reduced at 212°, from fifteen atoms to seven, by the escape of eight atoms of water. Of the seven atoms retained one is basic, and therefore expelled with difficulty ; but from a variety OXALATES, NITRATES, PHOSPHATES, SULPHATES, AND CHLORIDES. 67 of experiments which I have performed it appears probable (although I have never attained very precise results) that the other six atoms go off in pairs at different tem- peratures between 212° and 350° Fahr. But even at 410° the quantity of water re- tained by this salt was sensibly above one atomic proportion. We may with consi- derable probability represent the consecutive combinations of this salt with water by such a formula as the following : Mg2 HP + 2H + 2H + 2H + 8H. Besides the preceding salt there is a tribasic phosphate of magnesia, which is ob- tained as an insoluble precipitate on mixing tribasic phosphate of soda with sulphate of magnesia. Of this salt the whole three atoms of base are magnesia, as its name implies. Dried at 212° it retains five atoms of water. At a red heat it glows, but it continues soluble in acids even after exposure to a white heat. But I did not succeed in forming the other tribasic salt, containing two atoms of water and one atom of magnesia as bases, which is wanted to complete the series. Such a salt does not ap- pear to exist. It may be mentioned here in reference to the monobasic phosphate of magnesia (metaphosphate of magnesia), that although this salt does not present itself on mixing the monobasic phosphate of soda with the sulphate of magnesia, yet it is readily pre- cipitated in the form of a soft viscid body, on using the acetate of magnesia instead of the sulphate. 4. Tribasic Phosphate of Magnesia and Ammonia. (Ammoniaco -magnesian Phosphate .) Mg2 NH4 P -f 2 H + 10 H. This salt is the well-known granular precipitate formed on adding a salt of mag- nesia to any soluble tribasic phosphate with which ammonia or a salt of ammonia has been mixed. I was much interested in ascertaining the true constitution of this salt, and have carefully analysed seven or eight different specimens of it, prepared with and without free ammonia in the liquors. The result is that only one tribasic salt of these constituents exists, although two have often been admitted ; while in this com- pound there exists only one atom of ammonia instead of two, as M. Riffault has supposed. I subjoin the preparation and analysis of one specimen of this salt. 350 grains of crystallized phosphate of soda, 100 grains of chloride of ammonium, and 200 grains of aqua ammonite were dissolved together in four pounds of cold water, and 200 grains of crystallized sulphate of magnesia were added to that mixture. The precipitation was gradual, and the liquor remained alkaline. The precipitate was slightly washed with cold water, and afterwards dried in the air for ten days, the thermometer being 65° Fahr., without artificial heat. The true proportions of water, which this and many other precipitates affect, have often been mistaken, and definite hydrates not obtained, from using hot solutions in their preparation. Of this preci- 68 PROFESSOR GRAHAM ON THE CONSTITUTION OF pitate 26*8 grains lost by ignition 14*5 grains, or one part of the precipitate contains 0*541 volatile matter. For the ammonia, the volatile matter from 9*65 grains of the precipitate was sent over quicklime contained in a tube, so as to arrest the water. The loss, or the ammonia, amounted to 0*67 grain, or to 0*0695 of the precipitate. Hence this precipitate consists of Theory of Mg2 NH‘P-f 2H+ 10 H. Anhydrous salt . . . 45*90 45*85 Ammonia .... 6'95 6*98 Water 47 15 47*17 100* 100* From the manner in which this specimen of the salt was prepared, it should con- tain the maximum proportion of ammonia of which the salt admits, and yet that pro- portion is one atom only, and not two, as it was estimated by Riffault. A salt of the same composition was obtained from the same materials, omitting the caustic ammonia. In that case the product was not so abundant, and the mother liquor re- mained acid from the production of tribasic phosphate of water and soda, which has an acid reaction. When this salt, contained in a little retort, is heated in a very gra- dual manner to 212° by means of a water-bath, it is possible to distil over ten atomic proportions of the water without any ammonia whatever. Of the three atoms of water which remain, (the whole quantity originally present in the salt being thirteen atoms,) one appears to be combined with the ammonia in the formation of oxide of ammonium, while the other two are the constitutional water of the tribasic phosphate of magnesia and water. It appears, then, that this salt is not a double phosphate, or combination of two phosphates, but that it is formed from the tribasic phosphate of magnesia and water, by the substitution of oxide of ammonium for the basic water of that salt ; and it is a tribasic phosphate of magnesia and oxide of ammonium. The oxygen in the mag- nesia is double that in the oxide of ammonium. This salt is the type of a class of tribasic phosphates, in which the magnesia is re- placed by the other oxides, which are isomorphous with that base. Two of these salts were discovered and carefully examined by Dr. Otto of Brunswick #. Dr. Otto’s analysis of what we may call the tribasic arseniate of manganese and ammonia corresponds exactly with the analysis given above of the magnesian salt, except that he derives only twelve instead of thirteen atoms of water from his salt. The deficiency in the proportion of water found by him, I attribute to the use which he made of hot water in washing his salt. His analysis of the tribasic phosphate of the protoxide of iron and ammonia is par- ticularly interesting, as it proves that this salt is precipitated, containing no more than three atoms of water, or exactly of the composition of the magnesian salt dried * Journal fur Praktische Chemie von Erdman und Schweigger-Seidel, 1834, p. 409. OXALATES, NITRATES, PHOSPHATES, SULPHATES, AND CHLORIDES. 69 at 212°, as we have described. The constitution of this salt of iron I would therefore represent by the formula Fe2 NH4 P + 2 IT. In the same paper Dr. Otto describes another extraordinary phosphate, under the name of paraphosphate of soda, ammonia, and oxide of manganese, which does not belong to any class of phosphates that I have examined, but may possibly be a com- bination of two bibasic phosphates. Its constituents are 2 P, 2 Mn, NH4 and 6 H. It is prepared from bibasic phosphates, and would be said in the old language to con- tain pyrophosphoric acid. IV. Of Sulphates. In a former paper upon water as a constituent of sulphates *, I examined particu- larly the constitution of hydrated sulphuric acid and of the sulphates of the magne- sian class of oxides. All these salts contain one atom of constitutional water, which is displaced in the formation of the double sulphates by an atom of an alkaline sul- phate. This view is illustrated by the following formulae : Sulphate of water (acid of sp. gr. 178) H S IT Sulphate of magnesia Mg S H + 6 II Sulphate of magnesia and potash ....... Mg S (K S) + 6 H Sulphate of water and potash (bisulphate of potash) . II S (K S). It will be found upon experiment that the salts sulphate of magnesia and sulphate of zinc become anhydrous at much lower temperatures when mixed with sulphate of potash than by themselves, the sulphate of potash displacing the constitutional water of the other salt at a very moderate heat, although the salts are mixed in the state of dry powders. In that paper the opinion was supported, originally suggested 1 believe by M. Mi- tscherlich, that the bisulphate of potash is a double sulphate of water and potash, and therefore really neutral in composition. The only difficulty which stood in the way of generalizing this result, and maintaining that all the salts usually considered as bisalts are really neutral in composition, was the composition of the bichromate or red chromate of potash, a salt which unquestionably is anhydrous. Here, it might be said, is a true bisalt. But M. H. Rose has lately published some observa- tions in regard to anhydrous sulphuric acid, which, I think, afford a clue to the discovery of the true constitution of the red chromate of potash. It appears that the vapour of anhydrous sulphuric acid is absorbed by sulphate of potash and by chlo- ride of potassium, without decomposition, and definite compounds formed ; which, however, are destroyed by solution in water. Here we appear to have a class of * Edinburgh Transactions, vol. xiii. p. 297 ; or London and Edinburgh Philosophical Magazine, 3rd series, vol. vi. pp. 327, 417. PROFESSOR GRAHAM ON THE CONSTITUTION OF combinations of sulphuric acid with salts. Chromic acid, which is isomorphous with sulphuric, forms combinations which I consider as analogous to these. With the neutral or yellow chromate of potash it forms the red chromate of potash, and with chloride of potassium it forms M. Peligot’s salt ; which differ only from M. Rose’s corresponding combinations of sulphuric acid, in being more permanent. The supe- rior stability of these chromic acid combinations unquestionably depends upon the little affinity for water which their acid possesses, while the affinity of sulphuric acid for water is very great. Hence we may suppose that the red chromate of potash is not a direct combination of two atoms of chromic acid with one atom of potash, but a combination of one atom of chromic acid with one atom of yellow chromate of potash ; and it may be represented as follows : (K Cr) Cr. The red chromate of potash will thus belong to a new order of combinations, dif- fering essentially from proper salts, which contain an oxide as base. This salt, there- fore, cannot be adduced as militating against the law that “all salts are neutral in composition”; the only known exceptions to which law are, I believe, afforded by the anormal classes of phosphates, phosphites, and arseniates. I have devoted much time to the examination of subsulphates of the magnesian % class of oxides, particularly of the subsulphate of zinc and the subsulphate of copper. These salts were generally formed by the partial precipitation of sulphate of zinc or sulphate of copper by means of caustic potash. They have both a disposition to carry down sulphate of potash, which is never entirely removed from them by washing ; while one of them, the subsulphate of zinc, is itself decomposed by washing. When most successfully prepared, they were found to contain four atoms of metallic oxide to one atom of acid, (instead of three atoms oxide, as M. Berzelius supposed,) to- gether with four atoms of water. I have not hitherto been able to form a distinct idea of their constitution, or to decide between different views which may be taken of it. But the force with which water is retained in these subsalts is very remarkable. The subsulphate of copper loses no portion of its four atoms of water at 212°, and I have not been able to reduce the quantity of water retained by this salt so low as one atomic proportion, even at the melting point of lead. The constitution of the subsulphate of copper appears to be changed when it is made anhydrous by heat. In the progress of the desiccation of the salt, its colour passes from a dull blue to an olive green, and it finally becomes of a chocolate brown, and is then anhydrous. Water poured upon the brown matter comes off of a blue colour, dissolving out a considerable portion of the soluble sulphate of copper. It appears, therefore, that the water originally present in the subsulphate must discharge some important function in its constitution, the subsalt being obviously decomposed when made anhydrous. The Alums form a most important class of the sulphates, but I have never had it in my power to compare their constitution with that of the sulphate of alumina itself. OXALATES, NITRATES* PHOSPHATES, SULPHATES, AND CHLORIDES. 71 which is not easily obtained in a crystallized state. This salt, however, is described as containing eighteen atoms of water, while the alums have twenty-four. At present I would merely throw out the conjecture, that in the alums we may have simply an alkaline sulphate with the sulphate of alumina attached, that salt carrying along with it its whole water of crystallization, and acquiring six atoms more. The quantity of water in potash alum may be reduced by efflorescence to six atoms in a stove of the temperature of 1 50° Fahr. Hence potash alum may perhaps be represented as follows : K S + (A1A1 S3’ + 6 H + 18 II). I have shown by an analysis conducted in very favourable circumstances, that soda- alum contains, like potash-alum, twenty-four, and not twenty-six atoms of water. V. Of Chlorides. The affinity which the hydracids exhibit for water is weak. Of the lower hydrates of muriatic acid we know nothing, the volatility of the acid putting it out of em- power to form and examine such hydrates ; but it is likely that they will correspond with the hydrates of the chloride of magnesium, &c., which can be examined. The law in the case of the chlorides of the magnesian class of metals appears to be, that they have two atoms of water pretty strongly attached to them, and whicii we may consider as constitutional. Thus chloride of copper crystallizes with two atoms of water, and with no lower proportion ; but several chlorides of this class have two or four atoms more, the proportion of water advancing by a multiple of two atoms. 1. Chloride of Copper. CuCl H2. The blue prismatic crystals of chloride of copper become brown and lose the greater proportion of their water at a temperature not exceeding the boiling point of water. Fifteen grains of the crystals, exposed to a much higher temperature, lost 3*23 grains of water, leaving 11*77 grains of chloride of copper; and when this quan- tity of chloride of copper was exposed to the atmosphere, it quickly recovered 3*16 grains of water, and resumed the blue colour of the crystallized salt. I believe this method of reabsorption, in the case of constitutional water, often to give hydrates of which the composition is even more exact than if they had been obtained from solu- tion, owing to the absence of that water, which is often mechanically interposed be- tween the plates of crystals. The hydrated chloride of copper obtained in this way consisted of Theory of CuCIH2. Chloride of copper . . . 11*77 100. 100. Water 3*16 26*85 26*84 14*93 126*85 126*84. 72 PROFESSOR GRAHAM ON THE CONSTITUTION OF 2. Chloride of Manganese. MnCl H2 + 2 H. Experiment. — Of the flesh-coloured crystals, 15*53 grains, precipitated by nitrate of silver, gave 22*57 grains of chloride of silver, equivalent to 5*56 chlorine, or to 9*92 chloride of manganese, which leaves 5*61 grains water in the salt, or 36’] 2 per cent, of water. Now a chloride of manganese with four atoms of water would con- tain 36*33 per cent, of water. This salt readily lost half its water when dried at 212° in open air, or when dried over sulphuric acid in the vacuum of an air-pump at the ordinary temperature. But when the exposure of the salt in such circumstances was long protracted, a little of the constitutional water also was lost. 3. Protochloride of Iron. Fe Cl H2 + 2 H. In three experiments made upon different specimens of crystallized protochloride of iron, all newly and very carefully prepared, 13*69 grains chloride of silver were precipitated from 9*72 salt, 17*20 chloride of silver from 12*44 salt, and 15*75 chlo- ride of silver from 11*21 salt. These experiments almost coincide in their results, which are, that 1 part of the salt contains 0*3466, 0*3463, and 0*3461 of chlorine. But such proportions of chlorine are decidedly under the proportion which a neutral salt with four atoms of water should contain, namely, 0*3593 chlorine. Indeed, the quantity of water in the salt is indicated by these experiments to be four and a half atomic proportions almost exactly. By crystallizing from an acid solution Bonsdorff has lately obtained this salt in a state of purity, and containing four atoms of water. 4. Chloride of Magnesium. MgCl H2 + 4 H. Of the crystals of this salt, which are decidedly deliquescent, 12*65 grains were found to contain 4*29 chlorine ; or the salt contains 33*91 per cent, of chlorine, which approaches sufficiently near to the theoretical proportion 34*69 per cent., supposing the salt to contain six atoms of water. 5. Chloride of Calcium. CaCl I1!2 + 4 H. The crystals of this deliquescent salt, dried in vacuo till they began to effloresce, were found to contain six atoms of water, the proportion usually allotted to them ; but it is remarkable, that, continued in vacuo over sulphuric acid for ten days during OXALATES, NITRATES, PHOSPHATES, SULPHATES, AND CHLORIDES. 73 the heat of summer, the crystals became opake and of a talky lustre, without being disintegrated, and their proportion of water was reduced to two atoms. 6. Double Chloride of Copper and Ammonium. Nil1 Cl + Cu Cl H2. Hydrated chloride of copper dissolved with chloride of ammonium, in the propor- tion of eleven of the first to seven of the last, readily affords a double salt, in which we appear to have an atom of chloride of ammonium with an atom of the hydrated chloride of copper attached. This double salt is less soluble than the chloride of copper itself, and retains more strongly the two constitutional atoms of water of that salt ; illustrating in both of these points what appear to be two very general occur- rences : namely, 1 st, the reduced solubility of double salts ; and, 2nd, the closer attachment which constitutional water exhibits for a salt when that salt itself enters into combination. Analysis. Theory of NH4Cl + CuClH:. Chlorine 51 -03 51 -08 Copper 23-35 22‘83 Ammonium (N H4) . 13-20 13-10 Water ...... 12-09 12-99 100-67 100- The water cannot be entirely expelled without risking the sublimation of chloride of ammonium, and hence the quantity of water obtained is under the truth. The cop- per is above the truth, from having been precipitated by caustic potash in the state of oxide, which last when so obtained always retains a little potash. There is a corresponding chloride of copper and potassium, but I did not succeed in forming analogous double salts with chloride of magnesium or with any other chloride of the class in the place of the chloride of copper. The chlorides have probably their analogues in the cyanides, but with the single cyanides of iron, copper, &c., we are less acquainted. It is worthy of remark, how- ever, that the disposition of the protocyanide of iron and of the cyanide of copper to combine with two atoms of cyanide of potassium may depend upon the cyanides of iron and of copper possessing two atoms of constitutional water, (like the correspond- ing chlorides,) which are displaced by two atoms of the alkaline cyanide in the for- mation of the double cyanides. In “ ferrocyanic acid” we have the protocyanide of iron combined with two atoms of hydrocyanic acid, in the place of the same two atoms of water. MDCCCXXXVII. L "1 J [ 75 VII. Researches on the Tides —Seventh Series. On the Diurnal Inequality of the Height of the Tide, especially at Plymouth and at Singapore ; and on the Mean Level of the Sea. By the Rev. W. Whewell, M.A. F.R.S., Fellow of Trinity College, Cambridge. Received March 7, — Read March 9, 1837. THE Inequality of the Tides which is the subject of the present paper, though theoretically very curious, and practically very important, has hitherto been hardly noticed, and its laws have never been generally stated. By means of the materials which I have had in my hands, I have not only been able to obtain a rule agreeing with the observations to an extraordinary degree of precision, but I have found and analysed a case in which this inequality assumes a very remarkable form, so as mate- rially to disguise the general circumstances of the tides, and to explain other cases in which the usual features are entirely obliterated. The inequality of which I speak is the Diurnal Inequality, by which the tide of the morning and evening of the same day differ. The difference is often very consider- able, especially in the height of the water ; and naval officers have often found the preservation or destruction of a ship to be caused by this difference, without being aware that it was subject to steady rules, and was capable of being predicted. The small number of places for which I have been able to procure the proper observations will not permit me at present to state the circumstances of the inequality as they occur all over the surface of the ocean ; but I am, by fortunate circumstances, able to trace its laws in some very remarkable instances, situated in very widely separate regions of the globe. Sect. I. Diurnal Inequality at Plymouth. I will first treat of the diurnal inequality as it appears at Plymouth, at which port good tide observations are regularly made under the direction of Mr. Alexander Lumsdale and Mr. William Walker, the Master Attendant and Assistant Master Attendant of the Dock-yard. It has long been known that both at Plymouth and at other places there is com- monly a difference in the morning and evening tide of the same day. It is stated by Colepress in 1668*, that at that port “ the diurnal tides from about the latter end of March till the latter end of September are about a foot higher in the evening than in the morning ; that is, every tide which happens after twelve in the day before twelve at * Philosophical Transactions, vol. iii. p. 633. L 2 76 THE REV. W. WH EWELL ON THE nighty and vice versa the rest of the year.” But we shall soon see that this way of ex- pressing the fact, by speaking of morning and evening tides, is quite inaccurate. It is easily seen that the theory of the tides, which supposes them to be produced by the ocean assuming its form of equilibrium under the influence of the moon’s attraction, would give a diurnal difference of the tides: for if the moon have 20° north declination, the tide spheroid will have one pole in latitude 20° north, and the other in 20° south latitude ; and as the earth revolves, a place in 50° north latitude will have the tide which belongs to these two poles alternately : and as it is 30° from one pole and 70° from the other, the two tides will be very unequal. Now it has been found, with regard to all the other inequalities of the tides, that they follow the laws of the tides of the equilibrium-theory, although the constant ele- ments (the magnitudes and epochs) can be determined only by observation. Finding that the diurnal inequality was very clearly marked in the Plymouth observations, I did not hesitate to at mpt to trace its laws, by assuming this kind of correspondence with the equilibrium- theory. The result confirmed the assumption in the most striking manner, as I shall show. According to the equilibrium-theory, the tide which belongs to a south transit of the moon should be the greater (of the two on the same day) when the moon’s decli- nation is north ; when the moon crosses the equator, the difference of the two tides vanishes ; when she has south declination, the tide which belongs to her south transit is the smaller. The contrary (as to greater and smaller) will be true of the tide which belongs to the north or inferior transit. We cannot know, except by observation, to what transit of the moon any tide belongs ; but it is manifest that if we begin with any tide, the tides must belong alter- nately to south and north transits, and therefore the above alternation of greater and smaller tides, as the moon has north or south declination, must come into view. Accordingly I set off the observed heights of high water at Plymouth as ordinates of a curve, as seen in Plates II. and III. The zigzag form of the lines, appearing, vanishing, and reappearing, about once a fortnight, with great steadiness, showed that the diurnal inequality really existed in the observations. A line was drawn by the eye , cutting off from these zigzags equal portions above and below, and this was taken as the mean high water cleared of the »/•<•/, / Ij I. v /> / drf<7 ,i //»/// § 77jfv ■/>//• .// !> 1 Mean Level I* I T after S. Tran torrfirsiJ Ij I DIURNAL INEQUALITY OF THE HEIGHT OF THE TIDE. 77 vanish when the moon is in the equator. But it appeared that in fact the diurnal in- equality did not vanish till about four days after that period. By taking the moon’s declination four days anterior to the day of observation, and reducing it to a proper scale, it was found that the amount of the diurnal inequality could be represented with great accuracy, as may be seen in the Plates, which are spe- cimens of a comparison of this kind made for the whole of the years 1833 and 1834. It is to be observed, however, that the calculation of the diurnal inequality from the declination was made by means of a coefficient which was somewhat different in different months. Thus the usual multiplier of the declination for the diurnal in- equality of high water at Plymouth is i ; that is, 4° of lunar declination produce a difference of height of 1 inch : but in some cases the coefficient is i or more ; in others it is i. These differences appear to arise in part from the height of the tide itself; for the inequality is theoretically proportional to the whole lunar tide ; partly to the effect of the sun, according to different seasons of the year. Yet there appears to be still some other unexplained cause of the variation of this multiplier ; for there are differences in its value which cannot be referred to the causes just mentioned, and which operate, during a lunation or a semilunation, too uniformly to be acci- dental. We may take the coefficient at Plymouth to be i, which is the value on which the curves represented in Plate II. are constructed. I am persuaded that no one accustomed to the comparison of theoretical formulae with observation can look at those curves without being persuaded that the formula exhibits the true law of nature. As has been said, the declination of an anterior period has been taken. The period employed was the fifth lunar transit preceding the tide. Thus the diurnal inequality of January 6, 1834, is determined by the declination on January 2, at 51' 44m a.m., the time of the moon’s transit. The assumption of this period is confirmed by the gene- ral agreement of the results. From what has been said, the inaccuracy of the statements of this inequality, as an excess of the evening tide at particular seasons, and of the morning tide at other sea- sons, will readily appear ; for the high water at Plymouth is, on the average, five hours after the moon’s transit. Suppose the moon to move in the ecliptic, which is her average path : when the sun’s right ascension is five hours, (that is, about June 7,) the tide which follows the moon’s transit will follow the sun’s transit also, as soon as the moon is north of the equator ; that is, if the diurnal inequality were regulated by the moon’s place on the same day, the afternoon tide would be greatest ; and so it would continue till the moon was seven hours after the sun, at which period the tide would be twelve hours after the sun, and the tide following the moon would be- come the morning tide. But at the same time the moon would pass to the south of the equator ; and therefore the tide following the moon would be the smaller. Therefore in this situation the evening tide would be the greater during the whole lunation. But suppose the sun’s right ascension to be eight hours, (July 21,) then, when the 78 THE REV. W. WHEWELL ON THE moon begins to have north declination, the tide which follows her, and which is therefore the greatest, is three hours before the sun, and is a morning tide. When the moon’s right ascension becomes three hours, (that is, after about one eighth of a lunation,) the tide following the moon, which is still the greater, (because the decli- nation is still north,) becomes the evening tide. The evening tide continues the greater till the moon’s right ascension becomes twelve hours, when she passes to the south of the equator, and the tide following the moon, which is nine hours after the sun, and still the evening tide, becomes the smaller ; and this continues till the moon is seven hours from the sun, or in fifteen hours right ascension, at which period the tide which follows her becomes the morning tide, and the evening tide is again the greater. Thus in this position the morning tide is greater during six hours of the moon’s motion in right ascension (from the sun), and the evening tide is greater during the remaining eighteen hours ; that is, the evening tide is the greater during three fourths of the lunation. We might in the same manner trace the changes which take place in other posi- tions of the sun ; but this is unnecessary. The effect of the inequality may be calcu- lated by the tables which are added at the end of this paper. The height of low water at Plymouth is also affected by a diurnal inequality. It follows the same law as the inequality of high water ; its epoch is the same ; and its multiplier for May, June, July, August, 1834, is f, |, f, i, respectively. Sect. II. Diurnal Inequality at Singapore. By the Hydrographical Office of the Admiralty I was furnished with about a year’s observations of the tides of Singapore, from August 1834 to August 1835, made by Mr. W. Scott, the Master Attendant at that port, in pursuance of directions given by the Directors of the East India Company. These observations, from the very curious nature of the results to which they lead, I consider as more remarkable and valuable than any series of equal extent which has fallen under my notice. On laying down the heights of high water, it appeared that the early part of the series was very irregular, obviously from the imperfection of the observations ; but beginning with January 1835, the curve was tolerably regular ; and during the greater part of the subsequent time, the inequalities (which the observers could not know) were so clearly marked, and so steady in their course, that it was impossible to doubt the goodness of the observations. I proceeded to examine these in the manner already described for the Plymouth observations, and found a diurnal inequality nearly agreeing in law and in amount with that at Plymouth ; the only difference being, that instead of four days it was here found necessary to take the lunar declination a day and a half preceding the tide, or, more exactly, at the interpolated or north lunar transit which intervened be- tween the second and third south transit preceding the tide. DIURNAL INEQUALITY OF THE HEIGHT OF THE TIDE. 79 The amount of the inequality is nearly the same as at Plymouth, or rather greater, being, in the most regular parts of the series, one inch of height for every three degrees of declination. In these parts of the series (May, June, July, 1835,) the coincidence of the formula with observation is as close as at Plymouth. In other months (March, April, and August,) there are discrepancies; but we cannot consider these as throwing any doubt on the general correctness of the formulae, when we see how well it represents the observed diurnal inequality of low water, which is much more marked than that of high water. The diurnal inequality of low water at Singapore is of a magnitude which it would have been impossible to anticipate. It makes a difference' in many cases of not less than six feet between the height of the morning and evening tide ; the whole rise of the mean tide being only seven feet at spring tides, and the difference of mean spring and neap tides not more than two feet. This enormous diurnal inequality conforms, with deviations which are slight con- sidering its magnitude, to the same formula which we have already stated, the epoch being the same as that for high water ; that is, thirty-six lunar hours anterior to the last transit. The multiplier is different in different months, varying from f to 1 ; so that each degree of the moon’s declination produces an effect of nearly an inch in the height of low water, or two inches in the difference of two successive low waters. Sect. III. On the Diurnal Inequality at some other places , and on the General Laws of its Progress. I have not found any register of tide observations which exhibits the diurnal in- equality so clearly and regularly as Plymouth and Singapore, although I have tried many series observed in different parts of the world. It may however be detected in many, perhaps in most, places. The comparison of the circumstances of this inequa- lity in different places is curious and interesting, and especially the change which the epoch undergoes ; that is, the anterior period at which the moon’s declination corre- sponds to the amount and direction of the inequality. Bristol. — Mr. Bunt, who has bestowed very great labour upon the analysis of tide observations made at Bristol, has, among other inquiries, endeavoured to determine the diurnal inequality at that port. The results are not very regular, but they lead him to the conclusion that the inequality vanishes at nearly the distance of five days’ motion of the moon from her nodes ; that is, the epoch is Jive days. The amount of the inequality is five or six inches each way, at the greatest. Liverpool. — The diurnal inequality of the heights at Liverpool has been detected by Mr. Bywater from the observations, and introduced by him into his tide tables- I have already remarked in these Researches *, that the epoch of the diurnal inequa- lity at this port is about six days and a quarter ; but I do not conceive the determina- * Fifth Series. Philosophical Transactions, 1836, p. 133. THE REV. W. WHEWELL ON THE tion to be very exact, since the inequality has been tabulated by means of the calen- dar months, and thus has been referred to the moon’s mean motion in the ecliptic instead of being referred to her actual motion in her own orbit. The greatest effect is about half a foot in excess and in defect. Leith. — Tide observations have been made at Leith Harbour for several years. I have examined these for the diurnal inequality, but it does not appear with any great steadiness and regularity. Still its existence is very obvious ; and as the determina- tion of its epoch is a curious point, I attempted it in the following manner : Leith Tides, 1835. | Periods of Max. Diurn. Ineq. Tides after S. Transit. Middle of Max. Inequality vanishes. Moon’s dec. vanishes. Difference. Days. Feb. 15 to 25. less Feb. 20. Feb. 27. N. Feb. 15. 12 March 1 to 13. greater March 7. March 13. S. March 1. 12 March 15 to 25. less March 20. March 27. N. March 15. 12 March 28 to April 8. greater April 3. April 1 1 . S. March 29. 13 April 15 to 22. less April 19. April 26. N. April 11. 13 April 29 to May 9. greater (small) May 4. ' May 9. S. April 24. 15 May 1 1 to 18. less May 15. May 22. N. May 9. 13 May 22 to June 7. greater (small) May 30. June 6. S. May 21. [16] June 9 to 14. less June 12. June 17. N. June 5. 12 June 15 to 30. irregular June 23. June 29. S. June IS. [11] July 1 to 8. less (small) July 5. July 10. N. July 2. [8] July 12 to 19. greater (irreg.) July 16. July 20. S. July 15. [5] July 21 to 27. less (small) July 24. August 3. N. July 30. [5] August 10 to 17. greater August 14. August 22. S. August 11. 11 Aug. 26 to Sept. 4. less August 31. Sept. 6. N. August 26. 10 September 8 to 18. greater Sept. 13. Sept. 19. S. Sept. 8. 11 September 20 to 30. irregular Sept. 25. Sept. 30. N. Sept. 22. [8] October 1 to 11. greater October 6. S. October 5. DIURNAL INEQUALITY OF THE HEIGHT OF THE TIDE. 81 Among all the irregularities of the Leith tides, it is easily seen from the curves, when they are laid down, that there is a diurnal inequality, in consequence of which the tide following the south transit of the moon becomes alternately the greater and the smaller, as the moon’s declination changes from south to north, and the reverse. The times when this inequality is large can be picked out more decidedly than the times when it vanishes, and I therefore determined the epoch by means of the greatest in- equality, supposing the times when it vanishes to be midway between two successive maxima, as may be seen in the preceding Table. Rejecting those cases in which the inequality is very small or altogether irregular, it appears that the inequality vanishes twelve days after the moon’s inclination vanishes. This is certainly a very extraordinary result ; for it is difficult to conceive how the effect of the moon’s action can require so much time to manifest itself. Yet there can hardly be any doubt of the fact; for it is verified in 11 semilunations out of 17, and is inconsistent with none ; the variations in the interval being not greater than might be expected, supposing the law to be true. It may be observed, that by these variations the inequality is in some cases thrown back more than a whole semiluna- tion. Thus the inequality which prevails before April 26, and vanishes about that day, is not produced by the series of declinations which vanish on April 24, but by the series which vanish on April 11. To suppose the reverse would be impossible; for that would make it necessary to suppose that the inequality vanishes on Feb. 27, in consequence of the declination vanishing two days later, or March 1 ; that is, that the effect precedes the cause. , In the system of tide observations made on the coasts of Europe and America in June 1835, of the results of which an account was given in the Sixth Series of these Researches*, it appeared that the diurnal inequality on the east coast of Scotland was, during that semilunation, irregular, passing over a tide in the middle of the series. This and other anomalies in the diurnal inequality, as it appears on the coasts of the German Ocean, appear to show that the waters in that region are affected by the mixture of more than one tide. In the most material point, however, the observations of June 1835 confirm the results of our present inquiry ; namely, in showing that the diurnal inequality travels more slowly than the other inequalities. On the east coast of America, the changes of this inequality appear to be contempo- raneous with the corresponding changes of the moon’s declination, and the epoch is zero. On the coasts of Spain, Portugal, and France, it is successively two and three days. And this is quite consistent with the fact that this epoch is four days on the coast of Cornwall and Devonshire, Jive days at Bristol, six at Liverpool, and twelve at Leith. That the diurnal inequality should thus creep from place to place on suc- cessive days is difficult to explain ; but the laws of fluid motion are so little known, that we cannot collect from hydraulical views any good reason for doubting this curious fact. The fact is certainly not easily reconciled with our conception of the * Philosophical Transactions, 1836, Part II. p. 304. MDCCCXXXVIT. M 82 THE REV. W. WIIEWELL ON THE tides of remote places, as produced successively by the motion of the same “ tide- wave but it is already established beyond doubt, by the observations made on the two sides of the Atlantic in 1835, that tides which were supposed to be brought by the same tide-wave differ materially in their circumstances. As I have already stated*, “ On the 9th, 10th, and 1 1th of June 1835, when the diurnal inequality was great in America it was nothing in the West of Europe ; and on the 18th and 19th, when this inequality had vanished in America, it was great in Europe.” Are we to doubt whether the tide-wave which brings high water to America and to Europe at the same moment be the same wave ? A sound hydrodynamical view of all the circum- stances must enable us to decide ; but for this purpose more observations are needed, especially observations on the coast of America, where the diurnal inequality is great, and where, on several accounts, a knowledge of its laws would be interesting to us. Another remarkable circumstance in the progress of the diurnal inequality is, that it appears much more distinctly and steadily at some places than at others which are near them : nor does it seem easy to assign any rule which it follows in this respect. It is very marked and almost universal on the coast of the United States, and was conspicuous in the observations of June 1835 on the coasts of Spain and Portugal, the west coast of France, and parts of the west coast of Ireland. Yet at places inter- jacent among those at which it was thus displayed it could not be detected ; nor did the circumstances easily allow of my ascribing this to any defect of exactness in the observations. In like manner it is large on the east coast of New Holland, as we know from Cook’s account of his getting his ship off a reef by means of it ; and the north and south coasts of Australia appear to exhibit the extreme case of it, as we shall see. We might therefore suppose that it affects the whole of the Indian Ocean : yet at Keeling Island, in the centre of that ocean, it does not decidedly show itself. Such, at least, is the result of observations made by Captain Fitz Roy, from April 2 to April 8, 1836, with which I have been furnished by his kindness. Sect. IV. On extreme Cases of great Diurnal Inequality. If we consider the motion of the surface of the water in cases where, as at Singa- pore, the diurnal inequality is very great, we shall see that this motion is very different from the alternate equal ascent and descent which would occur if there were no such inequality. In order to exhibit this peculiarity, I have represented this motion in Plate IV. for Plymouth and for Singapore, as observed in the months of May and June. It will be seen that at Plymouth the curve of the motion of the surface oscil- lating upwards and downwards by nearly equal distances ; the main feature of in- equality is the difference of spring and neap tides, although the diurnal inequality is very clearly visible. But at Singapore the alternate oscillations make no approach to equality ; at some parts of the series the alternate tides seem to be on the point * Philosophical Transactions, 1836, Part II. p. 302. Range <>f tides . DIURNAL INEQUALITY OF THE HEIGHT OF THE TIDE. 83 of disappearing ; and the progress of this alternation affects the tides as much as the independent alternation of springs and neaps. It is easy to conceive the diurnal inequality carried a little further than it is at Singapore ; so that at a certain stage of it the alternate tides would vanish. This is equivalent to supposing the highest low water and the lowest high water to have the same height. There are statements of navigators respecting various places at which there is “ only one tide in twenty-four hours.” From what has been said it appears that this may happen during a part of each semilunation by the effect of the inequality now under consideration, but that it cannot in this way be constantly the case. I am fortunately enabled to throw some light on this subject by the kindness of Captain Fitz Roy. King George’s Sound on the south coast of New Holland is one of the places to which these Single-day Tides have been ascribed*. In March 1836 Captain Fitz Roy, aware of the interest of this position in respect to tide phenomena, caused observations to be made every half hour for some days, and for a portion of the time, every quarter of an hour. The result w'as that on March the 7th and 8th there were two very unequal tides, and that on the 9th and 10th there was only one tide ; but a recession and return in the high water, which had been barely perceptible on the 11th, became more and more marked on the 12th, 13th, and 14th, so as again to give two tides each day. Thus at this place it appears to be only at one particular period of the semilunation that we have a single-day tide, agreeably to our general view. I insert the curve of the motion of the surface at King George’s Sound in Plate IV. The single-day tides of Tonquin~f~ were referred by Newton to the interference of two tides, which arrive by different channels. The great diurnal inequality of Sin- gapore, which is in the same seas, appears to be clearly due to the effect of the moon’s declination ; and the establishment of this point, and the circumstances ascertained to occur in the reputed single-day tide of King George’s Sound, throw some doubt on the explanation just referred to, which cannot be removed till the tides of those seas have been more fully observed. Sect. V. On the Mean Height of the Sea. The question of the fluctuations of the mean height of the sea is not especially con- nected with the diurnal inequality. But as the curves which I had to draw in the course of this investigation give me the means of exhibiting very clearly these fluc- tuations, I will here say a word on the subject. In Plate II. a line is drawn representing the mean height ; that is, the height midway between low water and high water each day. It is obtained by taking the mean of the two curves of high and low water by which the diurnal inequality is cut off. The same is done for Singapore in Plate III. * Flinders, vol. i. p. 71. King, vol. ii. p. 380. f See Philosophical Transactions, vol. xiv. p. 162. M 2 84 THE REV. W. WHEWELL ON THE It appears that in all these cases the mean height of the sea is very nearly constant. This is most remarkable at Singapore, where, though the successive low waters often differ by six feet, the mean level only oscillates through a few inches. At Plymouth the mean level is not quite so steady. The fact is, that at that port the low water varies more by the difference of springs and neaps than the high water does ; and hence the mean level slightly follows the low water, and is lowest at spring tides, and highest at neap tides, or perhaps more exactly a day or two later. ‘£ The level of the sea at low water,” a phrase sometimes used by surveyors, is al- together erroneous, and may lead to material error. From the instances just quoted (and indeed from the nature of the case) it is certain that the mean height of the sea is far more nearly constant than low or high water, under whatever assumed condi- tions. A level surface drawn from any point (that is a surface of stagnant water) would probably be nearly parallel to the points of mean water at different places. This becomes more manifest when we consider that at places near each other the tide often differs greatly in amount. At St. David’s Head in Pembrokeshire the range of the tides is near thirty feet ; on the opposite coast of Ireland it is only two or three: if the sea were level at low water the difference of the mean heights on the two sides of the Channel (which is only about fifty miles) would be fourteen feet. Such an average elevation of one side of a narrow sea above the other is quite inconsistent with the laws of fluids. I cannot conclude this paper without again pointing out that a great number of curious facts in fluid motion are established by these Tide Researches, of which it may be hoped the theory of hydrodynamics will one day be able to render a reason. Why is it that at places near each other the range of the oscillations of the sea from lowr to high water is so different ? Why is it that the sun affects the low water at Ply- mouth more than the high water, and that the moon’s declination at Singapore affects the low water four times as much as the high water, while at Plymouth it affects it less ? Above all, why is it that while the effect of the sun, and of the moon’s declina- tion and parallax, in the monthly course of the tides, produces the effect due to the equilibrium of the forces in one or two days, the moon’s declination does not produce its effect upon the diurnal oscillation till after three, four, five, and six days ; and in some cases probably not till the moon is exerting forces which tend absolutely to re- verse the effect ? Table of the Diurnal Inequality of the Height of High Water at Plymouth. To be used with the moon’s declination four days anterior. For N. decl., add to the tide following moon’s S. transit, subtract from the tide following moon’s N. transit. For S. decl., subtract from the tide following moon’s S. transit, add to the tide following moon’s N. transit. Moon’s De- "1 clination / 0° to 4° 5° to 9° 10° to 14° 15° to 18° 19° to 21° 22° to 24° 25° to 26° 27° to 28° 29° 30° Diurnal In- 1 equality / Qin lin 2>n 3in ^.in 5in 6in yin 8in gin DIURNAL INEQUALITY OF THE HEIGHT OF THE TIDE. 85 Postscript. I will take the liberty of mentioning the only way in which it appears to me mechanically possible to conceive the slow propagation of the diurnal inequality which I have described in Sect. III. If we suppose equal semidiurnal tides to be propagated along the length of a wide canal ; and if we suppose, in addition to these, a transverse oscillation of the water to take place in the direction of the width of the canal, the time of this oscillation (from maximum to maximum) being a whole tide day; we shall have successive tides alternately greater and less by a diurnal inequality. And we may easily suppose this transverse oscillation to be propagated gradually and slowly along the canal, by the contact of the particles of the water. In this manner we may represent phenomena following laws like those above described. But it may be further observed, that we may conceive the semidiurnal tide, as well as the diurnal inequality, to be propagated along the canal by means of transverse oscillations, the time of this oscillation being half a lunar day ; and the rate of pro- pagation of this undulation may easily be supposed to be different from that of the diurnal oscillation. In this way we may conceive the possibility of the different in- equalities of the tides being propagated from place to place at different rates, and thus having different epochs, as from the recent researches on the subject contained in the Philosophical Transactions they appear to have. Moreover, it is by no means necessary, in order to make this explanation applicable, that the transverse undulations should be perpendicular to the direction in which the tide is propagated : they may be oblique to it at any angle, and the result will still be the same. It appears possible, also, that such a supposition may be modified, so as to explain other phenomena of the tides ; for instance, the smallness of the tides in the central parts of wide seas. But the application of such a supposition to the actual phenomena of the ocean, and the determination of those tracts of sea which must, on this view of the case, be looked upon as tide-canals, would be a matter of no small difficulty, even if our ma- terials were sufficient for the purpose , and would probably be impossible without more knowledge of the tides on the shores of the great oceans than has yet been published. Trinity College , Cambridge, May 5, 1837- • ' ■?' . . [ 87 ] VIII. On the Structure of the Brain in Marsupial Animals. By Richard Owen, Esq. F.R.S. Hunterian Professor of Anatomy to the Royal College of Surgeons. Received October 31, 1836, — Read January 26, 1837. THE brain in Mammalia is essentially characterized by the complexity and mag- nitude of the apparatus by which its different masses are brought into communica- tion with one another. With respect to size, the cerebral hemispheres are in many species proportionally inferior to those of Birds ; and in most Insectivorous and Ro- dent Mammalia they present an equally smooth and uniform external surface ; but notwithstanding the absence of convolutions and diminished size of the cerebral he- mispheres in such Mammalia, a large apparatus of medullary fibres is present, which connect together either the opposite hemispheres, or the distant parts of the same hemisphere ; and this apparatus, or great commissure, is superadded to the anterior, posterior, and soft commissures, which, with the exception of a very slight rudiment of the fornix, are alone developed in birds for the purpose of uniting the opposite hemispheres. In the higher Mammalia, in which the cerebral hemispheres acquire superior size and increased extent of surface by means of convolutions, the super- added commissural apparatus presents a corresponding development and a highly complicated structure ; its several parts being distinguished as the corpus callosum, fornix, and their intercommunicating laminae, termed the septum lucidum. The fornix, by means of its posterior crura and the intermediate medullary tract termed the lyra, brings the hippocampi majores into communication with each other, and with the posterior folds of the corpus callosum*'; by means of its anterior crura it establishes a communication between the hippocampi and the optic thalami ; and by means of the septum lucidum its connexion with the corpus callosum is continued to the anterior fold of that body-f. In the Human brain the fornix, though of complex structure and developed as a very distinct part, is of small size as compared with the corpus callosum ; while the delicate * “ The fasciculi from the fornix form in part the covering of the hippocampus, and in part its loose fold, the taenia hippocampi.” — Reil in Mayo’s Anatomical Commentaries, p. 116. “ L’envelope medullaire de la corne d’ Ammon se continue avec la partie posterieure du corps calleux, et en partie aussi avec le pilier posterieur de la voute : c’est dans ce dernier que va se jeter le corps frange tout entier.” — Meckel, Anatomie Descript, tom. ii. p. 679. f “ Ainsi la voute represente une chaine trbs complexe qui unit les deux hemispheres l’un avec l’autre sur plusieurs points, et qui, de plus, etablit une communication entre la partie anterieure et la partie posterieure de chaque hemisphere.” — Meckel, Anatomie Descript, tom. ii. p. 658. 88 MR. OWEN ON THE STRUCTURE OF laminae of the septum lucidum by which the fornix is connected with the corpus cal- losum, present an extent of surface corresponding to the degree to which the corpus callosum and fornix recede vertically from one another as they advance from behind forwards. In tracing the modifications of these different parts through the mam mi - ferous series, the disproportion of the fornix to the corpus callosum is found to de- crease as the parts, to the connexion of which they are subservient, alter in their re- lative size. For as the superincumbent masses of the cerebral hemispheres diminish in the placental Mammalia, the corpus callosum is proportionally restricted in its development ; while the hippocampi and their free processes, called the taenise hip- pocampi, maintaining a remarkable uniformity in their absolute size, the fornix also continues large, and undergoes modifications of form which more distinctly manifest its relation as a commissure to the hippocampi than its structure in the human brain would indicate. Thus in the brain of the Sheep the taeniae hippocampi, instead of being lost in the posterior crura of the fornix, are continued along its lateral margins, augmenting its breadth : they converge and unite above the anterior crura of the fornix, which here appear as small subordinate appendages sent off into the optic thalaini below, from the union of the taeniae above ; the taeniae are then again sepa- rated and are continued downwards and forwards into the anterior lobes of the hemi- spheres, bringing these parts into communication with the hippocampi behind, whilst the point of union of the opposite taeniae becomes continuous with the anterior fold of the corpus callosum above. As the corpus callosum and fornix recede vertically from one another in a less de- gree in most Mammalia than in Man, the two laminae of the septum lucidum are consequently of less extent, but are proportionally stronger ; they are formed not merely by the epithelium of the lateral ventricles, but by fibrous laminae extending from the anterior and upper surface of the fornix to the opposite surface of the corpus callosum. In the simple and depressed forms of brain, such as the Rodentia present, the fornix, or hippocampal commissure, and the corpus callosum, or hemispheric com- missure, are in contact, so that their uniting medium cannot with propriety be termed the septum lucidum. The corpus callosum is the principal bond of union between the opposite hemi- spheres, extending horizontally above the ventricles, its middle fibres passing trans- versely, while those of its extremities, which are more or less bent beneath its body, radiate, and all intermix, in apposition with the ascending and diverging fibres of the peduncles of the cerebral hemispheres. It has hitherto been considered as the great characteristic of the brain in the Mammalia, and, taking the human brain as the term of comparison, to be developed in the ratio of the magnitude of the cerebral hemispheres. In the placental Mammalia this is a pretty accurate expression of the relations of the corpus callosum ; and as the posterior lobes of the hemispheres are the first to disappear in the descending comparison, so the corpus callosum diminishes in longi- THE BRAIN IN MARSUPIAL ANIMALS. 89 tudinal extent from behind forwards, and thus the corpora quadrigemina, pineal gland, and posterior part of the optic thalami are successively brought into view on divari- cating the cerebral hemispheres in the different Mammalia which exhibit this pro- gressive degradation of the great commissure. The researches of Tiedemann, as is well known, have shown that the anterior part, which is the most constant in the mammiferous series, is that from which the deve- lopment of the corpus callosum commences in the human brain. The aim of the present paper is not, however, to trace step by step the various modifications of the commissural apparatus of the hemispheres through the mammi- ferous class, but is limited to the description of a remarkable modification in that apparatus in the brains of the marsupial animals, to the detection of which I was led by observing that the commissural system presented the essential difference between the brains of the oviparous and mammiferous Vertebrata, and by associating the greater perfection of the brain, resulting from the development of the great commis- sure with the placental mode of development in the true Mammalia. The connexion subsisting between placentation and high cerebral organization may be one of simple coincidence, yet it is certain that of all the great organic systems, the cerebral or sentient organ is that which alone offers a marked improve- ment of gradational structure in the animals developed by a placenta. An attentive study of the manners of different Marsupiata in confinement, and an inspection of the exterior forms of the brain in some of the species, induced me to allude in a former paper to an inferiority of intelligence and a low development of the cerebral organ as being the circumstances in the habits and structure of these singular animals which were most constantly associated with the peculiarities of their generative economy*. I have since derived the most satisfactory confirmation of this coincidence from repeated dissections of the brains of Marsupiata belonging to different genera ; and although unable to explain how a brief intra-uterine exist- ence and the absence of a placental connexion between the mother and foetus can operate (if it be really effective) in arresting the development of the brain, yet it is a coincidence which has been so little suspected, and is so interesting in various points of view, that I believe the evidence of it will be acceptable both to the physiologist and the naturalist. In order to obtain satisfactory proof of the difference in the structure of the brain in the marsupial and placental quadruped, I dissected and compared together, step by step, the brains of a Wombat and Beaver. These animals, as is well known, are of nearly similar bulk, and manifest so many mutual affinities in their structure, that they have been, and still are, by some naturalists, classed in the same order of Mammalia. The Wombat is, in fact, in all its exterior characters, save the mar- supial pouch, a Rodent ; and in its internal anatomy, especially its digestive organs, more nearly resembles the Beaver than do many of the true rodent animals. The * Philosophical Transactions, 1834, p. 358. MDCCCXXXVII. N 90 MR. OWEN ON THE STRUCTURE OF brain of the Beaver was also preferred for this comparison of internal organization, because on an outward inspection it would be pronounced to be the less highly organized of the two ; the hemispheres in the Wombat presenting a few convolutions (Plate V. fig. 3.), whilst in the Beaver they are perfectly smooth (Plate V. fig. 1.). In the Beaver, however, the cerebrum is extended further backward, though still leaving the cerebellum quite uncovered ; while in the Wombat a portion of the optic lobes (corpora quadrigemina) is also exposed. On divaricating the hemispheres of the brain in the Beaver, we bring into view, about three lines below the surface, the corpus callosum ; and on removing the ce- rebral substance to a level with this body, its fibres are observed to diverge into the substance of each hemisphere, in the usual manner, some bending upwards, but a greater proportion arching downwards, and embracing the cerebral nuclei ; the an- terior fibres radiating into the anterior, the posterior fibres into the posterior extre- mities of the hemispheres. (Plate VI. fig. 3.) The portions of the brain which are removed in thus tracing the extent of the corpus callosum, bring into view the corpora bigemina and the pineal gland ; but the optic thalami are concealed by the great commissure above described. On separating the hemispheres of the brain of the Wombat, not only the bigeminal bodies and pineal gland, but the optic thalami are immediately brought into view, and instead of a broad corpus callosum, we perceive, situated deeply at the bottom of the hemispheric fissure, a small commissural medullary band, m, (Plate VII. fig. 4.) passing in an arched form over the anterior part of the thalami, and extending be- neath the overlapping internal or mesial surfaces of the hemispheres, which thus appear, as in the Bird, to be wholly disunited. On gently raising the hemispheres from above the commissure, and pressing them outwards with the handle of a scalpel, the instrument passes into the fissure upon which the hippocampus is folded ; and on continuing the pressure the hippocampus is torn through, and the lateral ventricle is exposed. The mesial wall of the hemi- sphere is continued from the superior and internal border of the hippocampus, and is composed in the Wombat, as in the Bird, of a thin lamina of medullary substance analogous to the septum lucidum. In the Kangaroo, the mesial parietes of the lateral ventricles are stronger, being about two lines in thickness. The posterior transverse fibres of the commissure are continued outwards and backwards, beneath the more longitudinal fibres, which overlap them as they pass from the taenise hippocampi forwards to the anterior cerebral lobes. All the fibres of the commissure pass along the floor of the lateral ventricles into the substance of the hippocampi majores, which are of proportionally very large size. (See Plate VI. and VII. fig. 4, n .) Thus the commissure which is brought into view on divaricating the cerebral hemispheres in the Wombat is seen to be partly the bond of union of the two hippo- campi majores in the transverse direction, and partly of the hippocampus and anterior THE BRAIN IN MARSUPIAL ANIMALS. 1)1 lobe of the same hemisphere in the longitudinal direction. It also fulfils the other function of the fornix by sending down from the inferior surface two small nerve-like processes, which extend vertically, behind the anterior commissure, through the sub- stance of the optic thalami, near their mesial surfaces, to the corpus albicans, at the base of the brain. The superior view of the connexions of the hippocampal commissure of the Wom- bat is given at Plate VI. fig. 4. Returning to the Beaver’s brain, we raise the posterior thickened margin of the corpus callosum, and at the middle of its inferior surface we find it closely connected with the centre of a commissural band of fibres, arching over the anterior part of the optic thalami, and passing outwards and backwards along the floor of the lateral ventricles into the substance of the hippocampi, which are as largely developed as in the Wombat. The anterior part of the corpus callosum is bent downwards, and is attached along the middle line of its inferior surface by a uniting medium of medul- lary substance, representing the septum lucidum, to the hippocampal commissure or fornix. The teenise hippocampi, which form the lateral parts of this commissure, extend forwards, as in the Wombat, into the anterior lobes. The corpus callosum being removed, and the commissural fibres of the hippocampi being left behind (as shown on the left side at Plate VI. fig. 5.), the view of the Beaver’s brain now corresponds with that obtained in the previous dissection of the brain of the Wombat ; which we regard, therefore, as wanting the corpus callosum, septum lucidum, and consequently the fifth ventricle. The artery of the plexus cho- roides, in both the Beaver and Wombat, enters the lateral ventricle, where the hip- pocampus commences at the base of the hemisphere, and the plexus is continued along the under surface of the toenia hippocampi, and passes beneath the fornix, through the usual foramen, to communicate with its fellow in the third ventricle, immediately be- hind the anterior crura of the fornix, which are sent down in the Beaver, as in the Wombat, from the centre of the inferior surface of the hippocampal commissure. If we expose the lateral ventricle by removing its outer parietes in a marsupial and placental quadruped, as shown in Plate VII. figg. 4 and 5, in the Kangaroo and Ass, the hippocampus major ( n ), the tsenia hippocampi (o), the plexus choroides (p), and the foramen Monroianum (y) are brought into view. If a style be thrust trans- versely through the internal wall of the ventricle, immediately above the hippocam- pus, in the placental quadruped, it perforates the septum lucidum (q), and enters the opposite ventricle below the corpus callosum. If the same be done in the marsupial brain, the style passes into the opposite ventricle, but is immediately brought into view from above by divaricating the hemispheres, and is seen lying above the com- missure of the hippocampi. This commissure may nevertheless be regarded as representing, besides the fornix, he rudimental commencement of the corpus callosum ; but this determination does not invalidate the fact that the great commissure which unites the supraventricular n 2 92 MR. OWEN ON THE STRUCTURE OF masses of the hemispheres in the Beaver and all other placentally developed Mam- malia, and which exists in addition to the hippocampal commissure, is wanting in the brain of the Wombat : and as the same deficiency exists in the brain of the Great and Bush Kangaroos, the Vulpine Phalanger, the Ursine and Mauge’s Dasyures, and the Virginian Opossum, it is most probably the characteristic of the marsupial divi- sion of Mammalia. In the modification of the commissural apparatus above described, the Marsupialia present a structure of brain which is intermediate to that of the placental Mammalia and Birds, in which class the great commissure is wholly wanting, and the hemi- spheres, though comparatively larger than in many of the Mammalia, are brought into communication only by means of the anterior, posterior, and soft commissures, and a slight trace of the fornix or hippocampal commissure. Of the other peculiarities of the marsupial brain, the relatively large size of the anterior commissure is most worthy of notice ; its development is correspondent with the large size of the cerebral ganglion, which forms the chief origin of the olfac- tory nerve, and some of the anterior fibres arch forwards, and are directly continued into those nerves. In the position, superficial transverse fissure, and solidity of the bigeminal bodies, the marsupial brain adheres to the mammiferous type, as also in the exterior trans- verse fibres of the commissure of the cerebellum, forming the pons Varolii, the presence of which is in relation with the development of the lateral lobes of the cerebellum. Other minor points of difference between the brains of the Marsupiata themselves will be explained in the description of the figures. Meanwhile their agreement in so important a modification of the cerebral organ as the absence of a corpus callosum and septum lucidum, affords additional and strong grounds for regarding the Marsupiata as a distinct and peculiar group of Mammalia ; and when to this modification of cerebral structure are added the traces of the ovi- parous type of structure presented in the circulating and absorbent systems, together with the peculiarities of the osseous and generative apparatus, we may with reason suspect that distribution of the Marsupiata to be artificial and founded on an imper- fect knowledge of their mutual affinities which, from a modification of the teeth and extremities alone, would separate and disperse the species amongst corresponding groups of the placental Mammalia. Cuvier has observed that the marsupial group of quadrupeds embraces forms which typify different orders of the ordinary Mammalia and M. De Blainville regards them as forming, with the Monotremata, a division apart from the placental Mammalia. The metropolis of this subclass is the continent of Australasia, where the different carnivorous, insectivorous, omnivorous, and herbivorous genera act * “ Les Marsupiaux — nous paraissent devoir former un ordre a part, tant ils offrent de singularity dans leur economie, et surtout parceque l’on observe en quelque sorte la representation de trois ordres bien differents.” — R&gne Anim. i. p. 172. %/. Trans MD CCCXXXVH Plate V p.93 JC-'csSo. WomiaP la. THE BRAIN IN MARSUPIAL ANIMALS. 93 corresponding parts to those performed by the placental Mammalia on a larger theatre, in which the avoidance of more numerous and powerful enemies, or the capture of more varied and subtle prey, demands the manifestation of more courage, the practice of more address, and the possession of more resources than appear to be called for by the exigencies of the Marsupiata in their more limited sphere. Fig 1. 2. 3. 4. 5. 6. 7. 8. 9. Fig. 1. 2. Description of the Plates. PLATE V. External form. The upper surface of the brain of a Beaver ( Castor Fiber, L.). The upper surface of the brain of a Monkey ( Midas nifimanus, Geoff.). The upper surface of the brain of a Wombat {Phascolomys Wombatus, Bl.). The upper surface of the brain of a Kangaroo ( Macropus major, Shaw.). The upper surface of the brain of an Ursine Dasyure ( Dasyurus ursinus, Geoff.). The upper surface of the brain of a Virginian Opossum ( Didelphys Virgi- niana, Shaw). The base of the brain of a Beaver. The base of the brain of a Wombat. The base of the brain of a Virginian Opossum. From these figures it will be seen that the convolution of the surface of the hemispheres of the brain does not take place in proportion as the hemispheres themselves are developed in superficial extent. They are fewer, for example, in the Midas, in which the hemispheres extend, as in most of the Quadrumana, over the greater part of the cerebellum, than in the Kangaroo or Wombat, where the cerebellum is left quite exposed. The brains of two species of herbivorous and two of carnivorous Marsu- pials are figured in this plate, to show indications of superior development which distinguish the brain of the herbivora, in the greater proportional development of the cerebrum, its convoluted surface, and the smaller proportional size of the olfactory tubercles. In all the species, but espe- cially the carnivorous Marsupials, the greater relative size of the vermi- form process is deserving of notice, as indicating the approach to the oviparous type of cerebral structure : it is associated with a corresponding diminution of the pons Varolii, as is strikingly shown in fig. 9. PLATE VI. Side view of the brain of the Kangaroo. Side view of the brain of the Virginian Opossum. 94 MR. OWEN ON THE STRUCTURE OF Structure. Fig. 3. Brain of the Beaver, with the substance of the hemispheres removed to the level of the corpus callosum. 4. Brain of the Wombat, with the substance of the hemispheres removed to the level of the hippocampal commissure, except on the right side, where part of the thin internal wall of the lateral ventricle is left. 5. Brain of the Beaver, with the left cerebral hemisphere cut down to a level with the commissure of the hippocampus, and the lateral ventricle ex- posed. The corpus callosum has been vertically divided, and the left half removed, together with the hemisphere : the right hemisphere is entire. 6. A similar dissection of the brain of the Kangaroo, with the right hemisphere entire, and turned aside, showing the absence of the hemispheric commis- sure, corresponding to the corpus callosum of the Beaver. The small size of the corpus striatum, r, as compared with the Wombat and Beaver, is shown in this view. The posterior bigeminal bodies are the broadest, the anterior the longest, in this animal as in the Beaver and Wombat. PLATE VII. Fig. 1 . A vertical bisection of the brain of the Opossum ( Didelphys Virginiana, Shaw), showing The large proportional size of the anterior commissure,?/. 2. A vertical bisection of the brain of a Goose. 3. A lateral section of the left hemisphere, showing the lateral ventricle and hippocampus major in the Opossum. The roof of the lateral ventricle is raised, showing it to be formed by fibres arching over the hippocampus, and continued from the inner margin of that part into those which radiate from the corpus striatum externally. 4. A similar dissection of the brain of the Kangaroo. In this species the roof of the ventricle is proportionally thicker than in the carnivorous Opossum. Besides the diverging fibres of the crus cerebri, and those which pass in an arched form from the inner border of the hippocampus, over that body to the corpus striatum, there are others which form a thin layer, and pass into the taenia hippocampi, closely embracing the hippocampus : some of these are shown at x x. The general disposition of the hemispheric fibres is such, that, supposing them contractile, they would draw the superficies of the hemisphere to- wards the crus cerebri, as to a fixed point, and compress the bodies pro- jecting into the ventricles. 5. A similar dissection of the brain of the Ass. The dotted line shows the ex- tent of the corpus callosum. Ity.3. Beaver /inn/ Owen ,/, // JTane/jaroo. l'/n! MJCCC E OT /V.,.', / / /. £ / JTa.nya.roo Tzy. 6. Opo/sum, Jzy. O. Fiy.j. Wo7nJ>at. JJ?22. Bty.2. JV.°J2. Beaver ThiJ. Trans. MDCCCXXXVn. T’Jaa Wt.p. 36. Fip. / . TW- 2- ly .. 5. c Ass . * l%c,. Fra/. 2> . Opo/sitm. JCanaaroo. THE BRAIN IN MARSUPIAL ANIMALS. 95 The same letters indicate the same parts in each figure. A. Cerebral hemispheres. B. Optic lobes, or corpora quadrigemina. C. Cerebellum. * Place between the vermiform process and lateral lobes, where the medul- lary matter of the cerebellum is superficial. a. Olfactory lobes or ganglions. b. Pons Varolii, or cerebellic commissure. c. Corpus trapezoideum. d. Corpora pyramidalia. e. Crura cerebri. f. Corpus albicans. g. Infundibulum. h. Pituitary gland. 1 a. Natiform protuberance, giving off the external root of the olfactory nerve. 1 b. Pyriform protuberance, forming the origin of the internal root of the ol- factory nerve. 1 c. Medullary root of the olfactory nerve emerging from a longitudinal fissure in the natiform protuberance. i. Fissure dividing the external root of olfactory nerve from the superincum- bent hemisphere. 2. Chiasma of the optic nerves. 3. Third pair of nerves. 4. Fourth pair of nerves. 5. Fifth pair of nerves. 6. Sixth pair of nerves. k. Corpus trapezoideum. /. Corpus callosum, or commissure of the hemispheres. m. Fornix, or commissure of the hippocampi. n . Hippocampus major. o. Taenia hippocampi. o'. Anterior fibres of the taenia hippocampi continued into the anterior lobes of the hemispheres. p. Plexus choroides. q. Septum lucidum, or internal wall of the lateral ventricle (Plate VII. fig. 5.). r. Corpus striatum. s. Continuation of the lateral ventricle into the olfactory nerve. t. Optic thalami. u. Pineal gland. x. Part of a thin stratum of medullary fibres arching over the hippocampus major, and continued into the internal wall of the ventricle. 96 MR. OWEN ON THE STRUCTURE OF THE BRAIN IN MARSUPIAL ANIMALS. y. The anterior commissure. %. Soft commissure. m. Hippocampal commissure. cc. The third ventricle. (3. The iter ad infundibulum. 7. The foramen Monroianum. The iter ad quartum ventriculum. s. The val vula Vieussenii. The fold of the valve corresponding to the posterior commissure. [ 97 ] IX. On the Tides. By John William Lubbock, Esq., V.P.R.S. Received March 15, — Read March 16, 1837. In my last paper on the Tides I endeavoured to point out the remarkable agree- ment which obtains in some respects between Bernoulli’s theory and results obtained from observations at the London Docks. Since that time my attention has been directed to the following points : 1. To ascertain, from a discussion of the Liverpool observations with reference to a previous transit whether they present the same kind of agreement with theory as those of London. (See Tables I. to XII.) 2. To ascertain whether, by taking into account a greater number of observations, the results given in my last paper remain sensibly unaltered. (See Tables XV. to XXVIII.) 3. To ascertain whether the establishment of the port varies sensibly in different years, and wdiether the removal of the old Bridge has occasioned any difference at London. (See Tables XIV. and XXX.) Numerous tables have been computed for me, in order to elucidate these points, by Mr. Jones and Mr. Russell, having been enabled to procure their valuable assistance in these laborious investigations by means of a further sum of money placed at my disposal for the purpose by the British Association for the Advancement of Science, to which distinguished body I take this opportunity of offering my grateful acknow- ledgements. The succeeding transits of the moon being denoted by the letters A, B, C, D, E, F ; and F being the time of the moon’s transit which immediately precedes the time of high water at London, my last discussion of the London Dock observations was in- stituted with reference to transit B : the present discussion of the observations made at Liverpool between the 1st of January 1774 and the 31st of December 1792, by Mr. Hutchinson, has been instituted with reference to transit A-f-, or that which precedes the time of high water at Liverpool by about 2d 0h 20m*9. This paper con- tains, in fact, two sets of tables precisely similar; the one set deduced from 13,391 observations of high water made at Liverpool by Mr. Hutchinson, and the other set deduced from 24,592 observations of high water at the Wapping entrance of the * The former discussion by Mr. Dessiou, given in the Philosophical Transactions for 1835, was made with reference to the transit immediately preceding. t I had intended the transit B to be used as the argument : the mistake was not perceived until the work was too far advanced to make it worth while to have recommenced. MDCCCXXXVII. O 98 MR. LUBBOCK ON THE TIDES. London Docks made under the direction of the late Mr. Peirce ; the latter tables differing from those given in the Philosophical Transactions for 1836, Part I., chiefly by being founded upon nearly double the number of observations. The high waters at Liverpool considered in this paper occur about 48 hours after the transit of the moon to which they are referred ; the tides at London which are considered occur about 50 hours after the transit to which they are referred in this discussion, so that in fact all the intervals of the Liverpool Tables given in this paper ought to be increased by 36 hours, and all the intervals in the London Tables by 48 hours. The tide which makes high water at Liverpool arrives at the same instant somewhere on the north-east coast of Scotland, and at London about fifteen hours later. This is proved by the epoch of the semimenstrual inequality. I find by interpolation from Table II. the interval for the moon’s transit A d h m At 3 o’clock ... 1 23 40‘5 and at 9 o’clock ... 2 1 2-0 The difference is lh 21m“5, which converted into space = 20° 22' log tan 20° 22' = 9‘56965 = log {A). (See p. 117.) If we take the difference between the greatest and least heights = 5*52 from Table III., (E) = ^2) = 7*4353 for Liverpool, log (E) = 0-87130. If we take the greatest height = 17’66 from Table III., 17-66 = /)+{!+ iA)) (E) ~ D 4- {1'3712} (E) ; and hence definitively for Liverpool in the year 1786, log ( A ) — 9-56965, log (E) = 0-87130, 1) = 7*46, D being reckoned from the datum in the East Wall of the Canning Dock. And I find in the same manner for London in the year 1820 log {A) = 9-58418, log (E) = 0*64690, D = 16'69, D being reckoned from the sill of the London Dock gates at the Wapping entrance. I conceive that the best if not the only method of investigating alterations in the height of the land above the water in any given locality where the water is influenced by the tides, will be to examine carefully whether any alteration has taken place in the values of the constants D and (E) for that place, the height of high water being of course always reckoned from some fixed mark in the land. The semimenstrual * inequality of the interval at Liverpool presents the same re- markable agreement with observation which has been noticed before, while the form or law of the semimenstrual inequality of the height is also the same as that indi- * The semimenstrual inequality is an inequality of high water or of the semidiurnal wave. MR. LUBBOCK ON THE TIDES. 99 eated by the observations ; but in order to render the agreement complete, it would be necessary to change the epoch by half an hour*. This remarkable circumstance also obtains in the London correction, as may be seen by reference to the plate which accompanies my last paper. The results contained in the Tables here given are laid down in diagrams, with- out which they could not be so readily understood ; but as they are similar in nature to those contained in my last paper, they do not require an extended de- scription. The calendar month inequality at Liverpool, considered as resulting implicitly from the corrections due to changes in the declinations of the luminaries and in the sun’s parallax, agrees generally with the equilibrium theory, and with the results deduced from the London observations given in my last paper. The diagrams in Plate I. show that the spring equinoctial tides are greater than the neap equinoctial tides, and that the neap solstitial tides are greater than the spring solstitial tides, confirming what is stated by Laplace in the Exposition du Systeme du Monde, 5e ed., p. 83, and by Newton: “In quadraturis autem solstitialibus majores ciebunt sestus quam in quadraturis sequinoctialibus, eo quod Lunae jam in sequatore constitutse effectus maxime superat effectum Solis. Incidunt igitur sestus maximi in syzygias et minimi in quadratures luminarium, circa tempo ra aequinoctii utriusque. Et aestum maximum in syzygiis comitatur semper minimus in quadraturis, ut experientia compertum est.” Laplace says, “ Elies [les marees] augmentent et diminuent avec le diamtitre et le parallaxe lunaire, metis dans un plus grand rapport but the diagrams in Plate II. appear to confirm the truth of this passage only at neap tides. It is desirable to establish the laws which regulate the diurnal inequality in the height of high water in different parts of the globe ; at present the data are very insufficient. Mr. Whewell remarks, “that it would be easy to enumerate many actual cases in which the safety or loss of a ship has been determined by this inequality.” Mr. Whewell was the first specially to notice, in his examination of the results of the tide observations made on the coasts of Europe and America in June 1835, contained in the Philosophical Transactions for 1836, the changes which this inequality presents in passing from one place to another. This inequality depends chiefly upon the sign and amount of the moon’s declina- tion. The observations at London and Liverpool indicate no difference between tides corresponding to upper and lower transits, or between those corresponding to A.M. transits and transits P.M. six months afterwards ; hence in endeavouring to deter- mine the diurnal inequality at London and Liverpool, I have confounded in Tables XII. and XIII. the results corresponding to upper and lower transits, and those corre- sponding to A.M. transits and transits P.M. six months afterwards. I have also added to these those which ought, according to the preceding remarks, to differ only * Or, adopting Bernoulli’s views in other respects, the epoch of the correction for the height is not the same as that for the interval. 100 MR. LUBBOCK ON THE TIDES. in sign, and I have taken the mean of the whole for the result, as in the following example. Moon’s transit A. — Liverpool, Jan. July h m ft. 0 30 A.M. — -631 . . . P.M. +'57 substituting mean of all a.m. +'60 with proper p.m. — '42 J sign ft. -'56 + '56 + '56 -'56 4)2-22 •56 In the comparison of the heights in Plates I. II. and III. the London corrections have been multiplied by 1*7, that being the ratio of the quantities (E) for London and Liverpool, agreeably to the remark made in my last paper, p. 223. As the Lon- don discussion contained in my last paper was instituted with reference to transit B, and this discussion of the Liverpool observations has been made with reference to transit A, and as the tides which correspond to P.M. transits B correspond to A.M. transits A about twenty-five minutes less, in comparing our London and Liverpool results in all the Plates it was necessary to change the epoch, or to place the London corrections more to the left by half an hour, and to substitute in Plate III. for the London results corresponding to transits P.M. those corresponding to transits A.M. The diurnal inequality therefore, as it is laid down in Plate III. for London and Liverpool, has reference to the same tide or semidiurnal wave, making high water at London about fifteen hours later than at Liverpool. I have already remarked that the laws to which the wave producing the semi- diurnal inequality is subject, agree remarkably with Bernoulli’s theory. The equi- librium theory also implies the existence of another wave producing a diurnal in- equality. 2 ip — 2

' (for a given transit a.m. or p.m.). But this expression will not afford results agreeing with those which I have obtained from the observations at Liverpool if the declination of the moon be employed be- longing to the time of the transit A ; and it is necessary to employ the moon’s decli- nation at some time previous ; that is, several days before the high water under consideration. This is not at variance with what is stated in the Exposition , except that, although Laplace considers the two waves separately*', he has not, I think, referred distinctly to the change in the epoch for different places, or to the difference between the epoch of the original diurnal and semidiurnal waves, which produce the derived tides observed on our coasts. If, however, the diurnal inequality- wave travels more slowly than the semidiurnal inequality-wave, the epoch also will be different, and thus it may depend upon the moon’s declination several days earlier. If this view be correct, the diurnal inequality of high water has a maximum (geo- graphically) at those places on the coast at which the diurnal inequality-wave and the semidiurnal inequality-wave arrive simultaneously, and there will be places inter- mediate at which the diurnal inequality of high water is imperceptible, but where the diurnal inequality of low water is a maximum. This theory agrees with observation in giving no difference in the diurnal inequality for upper or lower transits. The diurnal inequality in the interval at Liverpool is inappreciable ; the diurnal in- equality in the height has been laid down in Plate III. from the approximate expression d h = B [A sin 2 cos — b then generally a < V . The character of the diurnal inequality is generally manifest in the observations of a single month, as may be seen by those which are laid down in Plate IV. When the change is remarked which takes place in the diurnal inequality in passing from Plymouth to Portsmouth, it will not excite surprise that this inequality should be so different for places more distant from each other, as for London and Liverpool. The calculations or predictions of the time of high water at any given place have long been made to depend upon what is called the establishment of the port, or a cer- tain quantity presumed to be constant and independent of the distances and declina- tions of the luminaries, but which may be influenced by local circumstances. It seemed to me desirable to ascertain carefully how much this quantity has fluctuated during the time the observations were made at Liverpool by Mr. Hutchinson, which we have employed, and since the observations at the London Docks were instituted. Tables XIV. and XXX., which give these fluctuations, have been computed by Mr. Russell. The changes of the Liverpool establishment, and the fluctuations of the average height of high water at Liverpool are given in Table XIV., and are exhibited in fig. 1. Plate V.: which shows the time and height of high water from 1802 to 1835 at the London Docks on the full and change of the moon; the moon’s parallax being 5 7', and the declinations of the luminaries 15°, i. e. the establishment and the fluctuations in the average height of high water during the same interval. All the intervals and heights have been carefully reduced to horizontal parallax 57' and declination 15°. The changes of the London establishment, and the fluctuations of the average height, are given in Table XXX., and are exhibited in fig. 2. Plate V. These fluctua- tions in the interval and in the height present an insuperable obstacle to extreme ac- curacy in tide predictions, unless they can be explained. “ In 1832 none of the lower portions of old London Bridge, (with the exception of two piers,) which prevented the natural flow of the tidal waters, were removed ; and in the second year (1833) almost the whole of that structure was cleared away as * See, for instance, the calendar month correction for the interval in January, and the correction for the height corresponding to H. P. 56'. MR. LUBBOCK ON THE TIDES. 103 regarded the masonry and starlings, although the section of the river was far from completed, many portions still remaining one or two feet above low-water mark, and which were finally removed in the year 1834*.” The time of high water appears now to be nearly as late as in 1804; in 1821 it was about ten minutes sooner. I am much indebted to Mr. Yates for notice of a very ancient tide table which exists in a MS. in the British Museum. It is in the Codex Cottonianus, Julius DVII., which appears to have been written in the 13th century, and to have belonged to St. Albans Abbey. It contains calendar and other astronomical or geographical matters, some of which are the productions of John Wallingford, who died Abbot of St. Albans a.d. 1213. At p. 45 b. is a table on one leaf, showing the time of high water at London Bridge, “ flod at london brigge”, thus : N.B. The numbers increase by a constant difference of forty-eight minutes. The first coiumn gives the moon’s age in days. Hence it would appear that high water at London on full and change was at that epoch 3h 48m, or more than an hour later than at present. The time of high water at London on full and change is given in Mr. Riddle’s Navigation and in other works 2h 45m : Flamsteed made it 3lu|''. .dStas Lunae. h m 1 3 48 2 4 36 3 5 24 4 6 12 28 ’ 1 24 29 2 12 30 3 0 Note. — On the Fluctuations of the Height of High Water due to changes in the Atmo- spheric Pressure. Read June 15. M. Daussy having ascertained that at Brest the ocean rises when the barometer is depressed, I verified the existence of the same fact at Liverpool and London, and I found that at Liverpool when the barometer falls ‘91 inch the tide rises 10T inches. As the range of the barometer is 3 inches^:, the correction which arises from change in the atmospheric pressure is by no means inconsiderable, its range being at Liver- pool about 33 inches. At London I have found that when the barometer falls ’9 inch * Rennie, Report on Hydraulics, p. 512. f See Philosophical Transactions, vol. xii. p. 12. + Between the tropics the fluctuations of the barometer do not much exceed one fourth of an inch, while beyond this space they reach to 3 inches. Daniell’s Meteorological Essays, p. 108. 104 MR. LUBBOCK ON THE TIDES. the tide rises 6 3 inches, and hence the I'angeoi the correction here is about 21 inches. Hence it is evident that in many inquiries relative to the tides, and particularly when observations are employed throughout only a limited period, the correction due to the atmospheric pressure may require to be attended to. Here, however, a question arises of some interest ; does the surface of the ocean rise in narrow seas simulta- neously with the depression of the barometer, or otherwise ? In order to acquire some information upon this point, I requested Mr. Russell to calculate carefully from our Tables the height of high water at Liverpool and London for May and June 1836, and to compare the calculations with the observations, which is done in the accom- panying Table, and the errors, together with the height of the barometer at Liverpool and London, are exhibited in fig. 3. Plate V. Table showing the difference between the Height of High Water as calculated, and the Heights derived from observations at the London and Liverpool Docks. 1836. May. Liverpool. London. 1836. May. Liverpool. London. 1836. June. Liverpool. London. J836. June. Liverpool. London. O - c. O- c. O- c. O- c. O - c. O- c. O - C. O- c. inches. inches. inches. inches. inches. inches. inches. inches. i — 1 — 1 17 + 1 1. + 6 17. + 11 + 9 — 7 + 5 — 8 0 — 3 + 4 + 12 + 9 2 — 11 + 13 18 — 6 — 1 2. 0 + 6 18. + 14 + 5 + 18 — 4 + 1 + 6 + 6 + 14 + 5 3 — 15 + 11 19 — 3 + 1 3. + 11 + 1 19. + 14 + 7 — 11 + 8 — 1 — 1 + 14 + 1 + 13 + 10 4 — 6 + 6 20 + 1 — 1 4. + 17 + 4 20. + 12 + 8 — 2 + 5 + 2 + 1 + 18 + 4 +- 12 + 5 5 — ■ 1 + 2 21 + 3 + 4 5. + 14 + 8 21. + 11 + 5 — 4 + 5 + 3 + 5 + 12 + 10 + 4 6 — 5 + 7 22 + 4 + 2 6. + 12 + 17 22. + 12 0 — 3 + 5 + 1 + 1 + 5 + 6 + 14 0 7 — 4 + 6 23 0 + 5 7. + 12 + 6 23. + 16 + 1 — 2 + 4 — 3 + 7 + 9 + 8 + 15 + 2 8 — 2 + 4 24 — 1 + 6 8. + 6 + 7 24. + 11 + 2 0 + 3 + 1 0 + 9 + 6 + 10 + 1 9 + 1 + 4 25 + 1 0 9. + 9 + 6 25. + 9 0 0 + 2 — 3 + 1 + 9 + 4 + 4 + 1 10 0 + 1 26 — 2 + 5 10. + 9 + 3 26. 0 + 3 — 1 — 3 — 2 + 1 T 5 + 5 — 2 + 2 11 0 — 5 27 — 2 1 11. + 3 27. — 1 0 — 5 — 2 — 1 + 5 + 6 + 2 + 1 12 0 28 — 0 12. + 5 + 4 28. + 3 0 — 3 + 1 — 2 0 + 3 + 2 + 2 + 2 13 — 5 0 29 — 3 0 13. + 1 + 3 29. 0 + 3 — 8 — 2 — 3 + 1 + 1 + 4 0 + 3 14 — 9 — 2 30 — 2 0 14. + 4 + 5 30. + 3 — 9 — 1 — 3 + 1 + 5 + 7 — 1 + 2 15 — 9 — 1 31 — 0 + 3 15. + 7 + 9 — 7 — 1 — 3 + 2 + 11 16 — 7 0 16. + 11 + 10 — 7 + 1 + 11 + 9 The above differences, O — C, are not the differences between Calculation and actual observation, but between Calculation and what it is presumed observation would be if freed of diurnal inequality by drawing an intermediate curve between those given in Plate TV. MR. LUBBOCK ON THE TIDES 105 Results deduced from Observations made at LIVERPOOL. Table I. ( a .) Showing the Interval between the Apparent Solar Time of the Moon’s Transit and the Time of High Water, and the Height of High Water at the Liverpool Docks, corresponding to the Apparent Solar Time of the Moon’s Transit A* in each month of the year, from 13,391 observations made at the Liverpool Docks, between the 1st of January 17/4 and the 31st of December 1792. January. Febi uary. Number of Obser- vations. Apparent Solar Time of Moon’s Transit A. Interval between the Moon’s Transit and the Time of high water. Height of Tide. Mean of Moon’s Declina- tion. Mean Horizontal Parallax. Number of Obser- vations. Apparent Solar Time of Moon’s Transit A. Interval between the Moon’s Transit and the l ime of high water. Height of Tide. Mean of Moon’s Declina- tion. Mean Horizontal Parallax. h m h m ft. in. h m h m ft. in. / 91 0 30-1 12 10-1 17 10-1 18-6 57-6 88 0 31-4 12 12-9 18 3-6 9-9 57-3 94 1 30-4 11 57-1 17 3-7 14-9 57-4 91 1 30-7 11 5 7-7 17 71 5-2 57-4 96 2 29-7 11 45-5 16 4-1 9-9 57-4 90 2 29-9 11 471 16 4-9 4-8 57-2 104 3 29-7 11 38-8 15 0-8 5-6 57-0 91 3 29-1 11 38-2 14 8-7 8-3 571 100 4 29-9 11 42-7 13 4-8 4-9 56-7 91 4 29-3 11 42-3 12 11-5 13-4 56-9 104 5 30 0 12 3-5 12 6-8 8-5 56-8 86 5 29-5 12 3-6 11 9-5 18-4 56-9 96 6 30-1 12 36-2 12 6-8 13-5 56-7 85 6 29-0 12 40-6 11 11-2 20-9 56-7 92 7 27-6 13 2-6 13 9-1 17-9 56-9 83 7 29-5 13 5-2 13 7-0 22-3 57-0 92 8 29-2 13 7-3 15 3-8 20-6 57-1 81 8 29-0 13 8-7 15 0*5 22-9 57-0 86 9 30-2 12 59-4 16 2-2 22-7 57 -5 83 9 29-8 12 59-4 16 6-3 21-7 57-2 89 10 30-2 12 44-7 17 3*5 22-6 57-6 81 10 30-4 12 43-9 17 7-9 18-9 57 -5 86 11 30-7 12 28-7 17 9-0 21-9 57‘7 87 11 30-3 12 28-2 18 2-8 14-9 57-3 Sun’s Declination S. 21°. Sun’s Declination S. 13°. March. April. 102 0 28-8 12 13-1 18 4-3 4-5 57-7 94 0 29-0 12 13-1 17 6-8 12-4 57-5 101 1 29-1 11 58-9 17 5-0 8-0 57-7 93 1 30-0 11 57-7 16 9-6 16-8 57-6 100 2 29-9 11 45-5 15 11-9 12-8 57-3 87 2 30-7 11 43-1 15 4-8 20-6 57-5 92 3 30-0 11 35-9 14 11 17-5 56-9 86 3 30’6 11 341 13 101 22-2 57-2 91 4 29-3 11 37-7 12 3-5 20-7 56-8 88 4 30-7 11 37-7 12 3-3 23-0 570 89 5 29-7 12 0-2 11 2-5 22-3 56-7 85 5 30-7 12 2-2 11 5-8 22-2 57-0 89 6 31-2 12 42-2 11 8-8 22-8 56-2 91 6 30-3 12 39-6 11 10-9 19-8 56-7 84 7 30-1 13 6-2 13 3-6 21-7 56-8 91 7 30-5 13 1-6 13 8-3 15-8 571 94 8 29-7 13 8-8 15 0-7 19-7 56-8 94 8 29-4 13 4-5 15 51 111 57-1 98 9 30-2 12 58-4 16 8-2 15-2 57-2 96 9 28-4 12 56-9 16 101 6-2 57-2 98 10 30-9 12 44-1 17 10-3 106 57-4 103 10 29-0 12 43-5 17 8-3 4-4 57-2 92 11 30-4 12 28-4 18 6-4 60 57-7 94 11 29-4 12 29 1 18 0-5 7-4 57-3 Sun’s Declination S. 2°. Sun’s Declination N. 10°. May. June. 87 0 28-6 12 12-8 16 9-0 20-3 57-3 82 0 28 -7 12 11 1 16 91 23-1 57-3 | 89 1 29-8 11 57-1 16 2-3 22- 1 57-4 85 1 28-9 11 56-8 16 3-3 22-1 57-3 83 2 30-6 11 43-1 15 3-3 22-8 57-5 87 2 29-4 11 44-2 15 5-9 19-5 57-2 87 3 29-3 11 35-2 14 0-7 22-1 57-3 92 3 28-6 11 38-7 14 5-5 15-9 57-1 95 4 29-4 11 38-9 12 11-7 20-0 57-1 99 4 30-0 11 44-5 13 8-0 11-5 57-1 96 5 29-7 12 3-2 12 41 15-1 57-1 96 5 29-7 12 4-6 12 11-2 6-4 57-0 101 6 28-9 12 35-7 12 10-8 11-9 57-1 108 6 30-2 12 35-4 13 30 4-8 57-0 106 7 29-5 12 57 1 14 1-6 6-6 57-2 97 7 30-9 12 57-2 14 0-5 7-5 57-2 103 8 30-0 13 1-3 15 4-4 4-5 57-0 96 8 30-1 13 2-6 15 2-5 13-4 57-3 101 9 30-5 12 55-5 16 5-7 7-2 57-3 91 9 30-4 12 57-2 16 2-0 17-0 57-4 98 10 313 12 43-0 16 11-6 11-9 57-2 85 10 29-8 12 45-1 16 8-0 20-4 57-6 89 11 29-9 12 29-3 17 3-5 16-9 57-4 84 11 29-5 12 29-4 16 9-4 22-2 57-3 Sun’s Declination N. 19°. Sun’s Declination N. 23°. 1 * The succeeding transits of the moon are denoted by the letters A, B, C, D, E, F ; F being the transit immediately preceding the time of high water at London. MDCCCXXXVII. P 106 MR. LUBBOCK ON THE TIDES Table I. (a.) (Continued.) i July. August. i Number P of Obser- | vations. 1 Apparent Solar Time of Moon’s Transit A. Interval between the Moon’s Transit anc the Time of high water Height of Tide. Mean of Moon’s Declina- tion. Mean Horizontal Parallax, Number of Obser- vations. Apparent Solar Time of Moon’s Transit A. Interval between the Moon’s Transit anc the Time of high water Height of Tide. Mean of Moon’s Declina- tion. Mean Horizontal Parallax. i h m h m ft. in. li m h m ft. in. 1 93 0 30-3 12 13-3 17 2-5 19-4 57-4 97 0 29-6 12 14-3 18 0*5 10-7 57-7 90 1 30-1 11 58-5 16 10-1 161 57-3 103 1 28-3 12 0-0 17 4-1 6-1 57-6 S ioi 2 29-8 11 45-4 16 M no 57-1 105 2 28-Q 11 47-0 16 5-0 4*5 57-3 101 3 30-8 11 41-8 14 9-0 6-4 56-9 100 3 28-4 11 40-1 14 9-5 7-0 56-9 1 100 4 29-7 11 45-3 13 8-2 4-7 56-8 100 4 28-7 11 41-3 13 11 12-8 56-8 8 102 5 29-0 12 5-2 12 8*5 7-5 56-8 93 5 28-8 12 2-4 11 9-4 17-5 56-7 § 99 6 29-1 12 37-0 12 7-9 12-7 56-9 93 6 29-0 12 39-7 12 0-4 20-6 56-7 97 7 29-7 13 0-8 13 10-8 17-2 57-1 84 7 29-1 13 4-9 13 4-7 22-2 56-9 f 92 8 30-6 13 6-2 14 111 20-7 57-1 90 8 29-3 13 9-7 14 9-0 22- 9 56-9 a 85 9 29-5 13 0-2 36 1-6 22-2 57-6 88 9 30-4 13 0-2 16 3-3 21-6 57-1 88 10 29-1 12 44-3 16 10-1 22-9 57-6 92 10 30-6 12 44-8 17 2-8 19-4 57-4 89 11 30-0 12 29-2 17 3-3 21-9 57-6 92 11 30-3 12 28-5 18 0-6 15-5 57-7 f Sun’s Declination N. 21°. Sun’s Declination N. 13°. I September. October. \ 98 0 30-5 12 13-5 18 4-9 4*5 57-6 95 0 28 -7 12 12-9 18 0-0 11-3 57-3 98 1 30-9 11 58-7 17 6*5 7-0 57-5 93 1 28-3 11 57-0 17 3-1 16-3 575 96 2 30-4 11 45-6 16 2-5 12-4 57-5 92 2 28-7 11 41-3 15 8-0 20-2 57-3 93 3 30-0 11 36-6 14 4-9 16-8 57-1 91 3 28-2 31 35-0 14 3-2 22-0 57-4 1 88 4 29-6 11 379 12 6-7 19-9 56-9 97 4 29-8 11 34-9 12 7-4 23-0 57-1 82 5 28-4 11 59-3 11 6-0 22-1 56-8 89 5 31'6 12 0-4 11 8-1 21-9 5 7-2 92 6 29-2 12 39-5 12 1-6 23-3 56-7 88 6 29-7 12 37-7 12 1-9 20-2 56-9 83 7 30-4 13 4-9 13 6-9 22-1 57-0 100 7 29-6 13 3-3 13 10-6 170 57-0 88 8 29-7 13 8-2 15 2-4 20-0 56-9 96 8 30-7 13 5-7 15 6-8 12-4 56-9 ! 91 9 29-9 12 58-7 36 9-2 16-0 57-2 100 9 30-0 12 57-3 17 0-5 6-9 571 94 10 29-7 12 44-0 17 11-2 11-2 57-4 98 10 29-3 12 43-5 17 8-9 4-5 57-3 | 98 11 30-2 12 28-5 13 3-8 6-5 57’5 100 11 28-7 12 28-8 18 6-8 6-6 57-3 _ Sun’s Declination N. 3°. Sun’s Declination S. 9°. November. December. 86 0 31-1 12 11-9 17 5-2 19-7 57-4 85 0 29-6 12 12-0 17 1-2 231 57-3 ! 82 1 30-6 11 56-0 16 6-8 22-2 57 -2 87 1 29-8 11 55-2 16 5-8 22- 1 57-3 j 83 2 29-9 11 41-7 15 6-4 22-9 57-2 86 2 29-1 11 42-7 15 7-6 19-3 57-1 85 3 29-6 11 34-1 14 2-8 22-2 571 97 3 28-7 11 38-3 14 9-2 15-8 57-1 84 4 31-3 11 37-2 12 10-7 20-2 57-0 101 4 30-3 11 41-6 13 6-0 110 56-9 | 89 5 310 12 2-4 12 5-5 16-4 57-1 104 5 30-1 12 3-7 12 10-3 6-6 56-9 j 100 6 30-2 12 37-5 12 11-5 12-3 56-9 106 6 30-2 12 35-8 13 2-0 4-9 56-9 98 7 30-0 12 57 -7 14 2-9 7-3 57-0 103 7 30-0 12 57-8 14 3-4 71 57-1 98 8 28 -7 13 2-4 15 9-6 4-5 571 101 8 29-5 13 2-3 15 7-7 12-3 57-3 99 9 28-4 12 54-4 16 11-7 6-2 57-3 90 9 29-1 12 57-0 16 7-7 16-3 57-5 94 10 28-3 12 43-9 17 8-0 11-6 57-4 93 10 29-1 12 45-1 17 3-3 20-1 57-5 i 94 11 29-9 12 28-8 17 101 16-5 57-4 85 11 30-3 12 28-2 17 6-3 22-2 57-6 Sun’s Declination S. 19°. Sun’s Declination S. 23°. Table II. ( b .) (Interpolated from Table I.) Showing’ the Interval between the Apparent Solar Time of the Moon’s Transit A, and the Time of High Water at the Liverpool Docks for each month in the year. Apparent Solar Time of Moon’s Transit A. January. February. March. April. May. June. July. August. Sept. October. Nov. Dec. Mean. h m h m h m h m h m h m h m h m h m h m h m h m h m h m 0 30 12 9-9 12 13-2 12 12-6 12 12-6 12 12-3 12 10-6 12 13-3 12 14-0 12 13-4 12 12-4 12 12-1 12 11-9 12 12-3 3 30 11 56-8 11 5 7-5 11 58-1 11 57-2 11 56-1 !1 56-2 11 58-2 11 59-1 11 58-4 11 56-1 11 55-9 11 54-9 11 57-0 2 30 11 44-8 11 46-8 11 45-0 11 42-4 13 43-4 11 43-8 11 45-2 11 46-1 11 44-9 31 40-6 31 41-4 11 42-3 11 43-9 3 30 11 38-8 11 3S-0 11 36-1 11 33-7 31 34-5 11 38-4 11 420 11 40-2 11 36-4 11 34-0 11 33-9 11 38-0 11 37-0 4 30 11 43-5 31 42-7 11 38-3 11 37-7 11 38-8 11 44-3 11 45-9 11 421 11 38-3 31 34-7 11 36-9 11 41-8 11 40-4 5 30 12 3-7 12 4-0 12 0-8 12 1-9 12 3-2 12 4-8 12 5-9 12 3-4 12 0-3 11 59-4 12 1-8 12 3-8 12 2-8 6 30 12 35 -S 12 40-7 12 40-6 12 39-0 12 36-4 12 35-3 12 37-4 32 39-8 12 39-5 12 37-7 12 37*8 12 35-6 12 37-9 7 30 13 2-8 13 5-3 13 5-7 i "3 1-7 12 57-7 12 57-5 33 11 13 4-8 13 4-8 13 3-4 12 57-7 12 58-0 13 1-7 8 30 13 7-5 13 8-7 33 8-3 13 4-7 13 1-3 33 3-3 13 6-4 13 9-5 13 8-0 13 5*5 13 2-7 13 3-0 13 5-7 9 30 13 0-2 32 59-7 12 58-7 12 56-9 12 56-1 12 57-9 13 1-1 13 0-5 12 59-0 12 57-5 12 53-6 12 57-6 12 58-2 10 30 12 45-2 12 44-5 12 44-7 12 43*5 12 43-5 12 45-6 12 44 7 12 45-3 12 44-3 12 43-6 12 43*9 12 45-4 12 44-5 11 30 12 29-1 12 28-4 12 28 -7 12 29-0 12 29-4 Mo 12 29-4 on’s Ho 12 29-4 (12 -. Par. 57'. 28-8 12 28-8 12 28-5 12 28-9| 12 28-5 12 29-0 MR. LUBBOCK ON THE TIDES. 107 Table III. (c.) (Interpolated from Table I.) Showing the Height of High Water at the Liverpool Docks, corresponding to the Apparent Solar Time of the Moon’s Transit A, in each month of the year. Apparent Solar Time of Moon’s Transit A. January. February. March. April. May. June. July. August. Sept. October. Nov. Dec. Mean. h in feet. feet. feet. feet. feet. feet. feet. feet. feet. feet. feet. feet. feet. 0 30 17-59 18-18 18-06 17-35 16-61 16-62 17-04 17-75 18-16 17-86 17-27 16-97 17-46 1 30 17-15 17-43 1712 16-55 16-02 16-13 16-71 17-07 17-33 17-02 16-50 16-35 16-78 2 30 16-17 16-33 15-87 15-21 15-33 15-40 16-05 16-26 16-02 15-53 15-45 15-57 15-77 3 30 15-06 14-66 14-13 13-76 13-93 14-38 14-81 14-79 14-37 14-06 14-18 14-70 14-40 4 30 13-51 12-98 12-35 12-30 12-93 13-63 13-75 13-14 12-59 12-58 12-92 13-55 13-02 5 30 12 65 11-82 11-33 11-49 12-30 12-93 12-78 11-89 11-56 11-62 12-43 12-90 12-14 6 30 12-69 1206 12-03 12-03 12-87 13-25 12-71 12-16 12-26 12-20 13-00 13-21 12-54 7 30 13-85 13-58 13-38 13-64 14-06 13-94 13-87 13-45 13-58 13-88 14-24 14-24 13-81 8 30 15-30 15-07 15-15 15-40 15-37 15-09 14-87 14-81 15-26 15-59 15-79 15-53 15-27 9 30 15-98 16-45 16-60 16-79 16-35 16-01 15-90 16-23 16-69 17-01 16-89 16-46 16-45 10 30 17-04 17-43 17-68 17-62 16-87 16-42 16-60 17-05 17-76 17-63 17-52 17-07 17-22 11 30 17-46 18-10 18-34 17-91 17-12 Mo 16-65 on’s Hor 17-03 . Par. 5 17-76 V. 18-11 18-45 17-67 17-28 17-66 Table IV. (d.) Showing the Interval between the Apparent Solar Time of the Moon’s Transit and the Time of High Water at the Liverpool Docks, corresponding to the Apparent Solar Time of the Moon’s Transit A, for every minute of her Horizontal Parallax. Hor. Par. 54'. Hor. Par. 55'. Number of Observa- tions. Apparent Solar Time of Moon’s Transit A. Interval between the Moon’s Transit and the Time of high water. Height of Tide. Moon’s Declina- tion. Number of Observe tions. Apparent Solar Time of Moon’s Transit A. Interval between the Moon’s Transit and the Time of high water. Height of Tide. Moon’s | Declina- 5 tion. a h m h m ft. in. h m h m in. 201 0 29-8 12 12-3 16 4-0 14-5 159 0 29-4 12 13-2 16 7-8 14-8 f 191 1 29-9 11 53-9 15 7-7 15-0 169 I 29 6 11 56-1 15 11-2 14-8 | 191 2 29-1 11 39-6 14 8-4 15-3 175 2 30-3 11 39-7 14 10-9 15-0 167 3 28-6 11 30-2 13 4-2 15-1 193 3 28-3 11 31-5 13 7-6 14-8 150 4 27 -7 11 32-2 11 11-5 15-5 236 4 30-4 11 34-1 12 3-0 15-8 108 5 29-0 11 58-0 10 10-4 15-3 242 5 30-2 12 0-2 11 3-0 14-8 120 6 30-1 12 41-6 11 4-0 16-3 266 6 29-1 12 40-7 11 6-9 15-3 133 7 30-8 13 8-5 12 8-6 14-8 214 7 28-5 13 6-7 12 10-9 15-3 174 8 29-3 13 12-7 14 2-3 15-8 208 8 29-1 13 13-7 14 7-3 15-5 | 179 9 29-3 13 4-9 15 5-1 14-8 186 9 29-8 13 4-6 15 9-7 15-1 ! 196 10 29-9 12 46-4 16 2-9 15-1 169 10 29-4 12 46-4 16 6-4 14-4 190 11 29-6 12 29-9 16 6-9 14-8 16S 11 29-6 12 29-4 16 9-1 14-7 Sun’s Declination 15° Sun’s Declination 15° Hor. Par. 56'. Hor. Par. 57'. 116 0 30-1 12 12-7 16 11-4 14-4 105 0 32-0 12 12-4 17 3-3 14-1 118 1 30-8 11 56-2 16 2-8 14-6 103 1 31-2 11 57-2 16 9-3 14-1 119 2 28-8 11 37-4 15 6-2 13-9 106 2 30-6 11 43-9 15 11-3 13-6 147 3 30-5 11 35-2 14 0-0 14-6 118 3 30-3 11 39-5 14 5-2 14-4 141 4 31-4 11 38-9 12 6-8 14-6 128 4 29-4 11 41-9 13 0-4 14-3 143 5 29-1 12 0-6 11 7-1 15-1 144 5 29-5 12 2-2 12 1-6 14-9 153 6 29-5 12 38-4 12 0-4 14-8 136 6 31-9 12 38-4 12 6-6 14-9 143 7 29-5 13 3-6 13 4-2 14-7 136 7 29-5 13 1-0 13 9-8 14-5 139 8 29-7 13 7-3 14 9-5 14-5 113 8 29-0 13 5-9 15 3-0 14-4 125 9 30-0 12 59-2 16 0-8 14-5 102 9 27-5 12 55-5 16 3-4 14-0 i 124 10 30-0 12 44-2 16 10-0 14-6 99 10 29-2 12 43 0 17 1-9 14-1 107 11 30-9 12 29-3 17 2-7 14-6 109 11 30-4 12 29-0 17 6-3 14-3 Sun’s Declination 15°. Sun’s Declination 15°. 1 p 2 108 MR. LUBBOCK ON THE TIDES Table IV. ( d .) (Continued.) Hor. Par. 58 / Hor. Par. 59'. Number of Observa- tions. Apparent Solar Time of Moon’s Transit A. Interval between the Moon’s Transit and the 'Time of high water. Height of Tide. Moon’s Declina- tion. Number of Observa- tions. Apparent Solar Time of Moon’s Transit A. Interval between the Moon’s Transit and the Time of high water. Height of 'tide. Moon’s Declina- tion. h m h m ft. in. h m h m ft. in. 92 0 27-4 12 13-7 17 6-2 13-5 94 0 29-1 12 13-3 18 4-9 14-0 101 1 28-6 11 58-0 17 2-2 13-8 98 1 31-7 11 58-4 17 8-2 141 101 2 30-0 11 46-1 16 01 14-0 114 2 30-9 11 47-3 16 6-5 14-6 12G 3 30-3 11 38-9 14 9-6 14-4 133 3 30-2 11 410 15 2-2 14-2 133 4 31-7 11 43-5 13 4-6 14-5 204 4 31-7 11 461 13 10-9 15-0 154 5 31-9 12 5-5 12 8-4 14-5 285 5 310 12 71 13 2-4 15-4 147 6 29-0 12 36-5 13 0-2 14-9 301 6 28-1 12 34-9 13 6-6 150 144 7 30-0 12 58-1 14 2-9 14-3 196 7 27-9 12 55-7 14 6-9 15-3 114 8 28-8 13 2-9 15 8-0 13-7 143 8 28-5 13 2-8 16 0-8 14-7 114 9 30-9 12 56-6 16 8-9 13-9 113 9 26-7 12 54-2 17 2-5 14-3 ! 104 10 29-9 12 43-3 17 6-2 13-4 97 10 28-3 12 44-0 18 0-8 14-4 88 11 28-7 12 28-6 17 8-9 141 98 11 29-5 12 29 0 18 61 13-8 Sun’s Declination 15°. Sun’s Declination 15°. Hor. Par. 60'. Hor. Par. 6P. 113 0 31-6 12 13-3 18 8-9 14-8 191 0 29-7 12 13-2 19 30 14-7 112 1 30-3 11 59-8 18 1-8 14-4 213 1 27-6 12 1-2 18 6-1 15-1 i 161 2 31-3 11 49-3 16 11-4 14-2 140 2 26-5 11 50-3 17 51 15-6 219 3 30-0 11 43-7 15 7-7 15-5 16 3 12-4 11 46-1 16 11 18-6 150 4 25-7 11 47-2 14 4-7 161 33 5 15-3 11 58-6 13 8-4 15-2 30 6 43-6 12 41-4 13 9-6 15-9 150 7 33-9 12 55-6 15 0-9 15-4 212 8 29-7 12 58-9 16 5-7 15-3 19 8 48-9 12 57-9 16 9-1 19-8 162 9 27-4 12 53-8 17 9-3 14-6 127 9 35-6 12 52-6 18 0-8 151 123 10 29-6 12 42-2 18 71 14-4 201 10 31-4 12 40-3 18 10-9 14-9 106 11 30-2 12 27 0 19 0-0 141 195 11 28-7 12 27-8 19 5-1 151 Sun’s Declination 15°. Sun’s Declination 15°. Table V. (e.) Interpolated from Table IV., and reduced to Moon’s Declination 15°. Apparent Solar Time of Moon’s Transit A. H. P. 54'. H. P 55'. H. P. 56'. H. P .57'. Interval. Height of Tide. Interval. Height of Tide. Interval. Height of Tide. Interval. Height of Tide. h m h m feet. h m feet. h m feet. h m feet. 0 30 12 12-1 16-31 12 13-0 16-64 12 12-6 16-92 12 12-8 17-23 1 30 11 53-9 15-64 11 560 15-91 11 56-3 16-22 11 57-3 16-74 2 30 11 39-5 14-70 11 39-6 14-93 11 36-9 15-42 11 43-6 15-86 3 30 11 30-2 13-32 11 31-4 13-58 11 350 13-99 11 39-3 14-40 4 30 11 330 11-94 11 34-4 12-32 11 38-4 12-58 11 41-7 12-98 S 5 30 11 58-6 10-88 12 0-1 11-24 12 11 11-59 12 2-5 1212 6 30 12 41-4 11-42 12 40-3 11-61 12 38-7 12-03 12 37 4 12-53 7 30 13 8-4 12-69 13 6-8 12-96 13 3-8 13-35 13 1-3 13-80 8 30 13 12-3 14-27 13 13-4 14-66 13 75 14-77 13 61 15-24 9 30 13 4-9 15-43 13 4-6 15-82 12 59-4 16-04 12 55-3 16-27 10 30 12 46-4 16-25 12 46-4 16-52 12 44-3 16-81 12 43 0 1711 11 30 12 29-8 16-57 11 29-3 16-75 12 29-5 17-21 12 29-2 17-49 H. P. 58'. H. P. 59'. H. P. 60'. H. 1 >. 61'. 0 30 12 12-9 17-41 12 13-0 18-34 12 13-7 18-74 12 13-1 19-16 1 30 11 575 17-08 11 58-6 17-64 11 59-8 18-12 12 0-6 18-49 2 30 11 45-8 15-95 11 47-4 16-54 11 49-3 16-93 11 49-9 17-40 3 30 11 38-7 14-77 11 40-7 15-16 11 44-0 15-67 4 30 11 43-0 13-39 11 45-8 13-95 11 45-8 14-37 5 30 12 4-4 12-69 12 6-7 13-24 6 30 12 37-0 13-03 12 35-9 13-58 7 30 12 58-4 14-20 12 55-9 14-65 12 54-6 15-02 8 30 13 3-3 15-62 13 3-0 16-10 12 58-7 16-51 9 30 12 57 1 16-65 12 53-8 17-24 12 53-4 17-81 12 53-6 17-96 10 30 12 43-6 17-42 12 43-7 18-06 12 42-2 18-57 12 40-6 18-89 11 30 12 28-3 17-69 12 29-0 18-43 12 27-2 18-94 12 27-4 19-45 MR. LUBBOCK ON THE TIDES 109 Table VI. (/.) Showing the Interval between the Apparent Solar Time of the Moon’s Transit and the Time of High Water, and the Height of High Water at the Liverpool Docks, corresponding to the Apparent Solar Time of the Moon’s Upper and LowerTransit A, p.m. and a.m. January. Upper Transits A, p.m. Lower (Interpolated) Transits A, a.m. Apparent Solar Time of Moon’s Transit A. Moon’s Parallax. Interval between the Moon’s Transit and the Time of high water. Height of Tide. Moon’s Declina- tion. Apparent Solar Time of Moon’s Transit A. Moon’s Parallax. Interval between the Moon’s Transit and the Time of high water. Height of Tide. Moon’s Declina- tion. h m / h m ft. in. h m h m ft. in. 0 30-1 57.6 12 113 18 7-6 S. 18-4 0 28-7 57-8 12 12-6 17 2-7 S. 19-2 1 30-4 58-0 11 56-3 18 5-3 S. 14.7 1 28-4 57-0 11 57-9 16 7-8 S. 14-7 2 28-7 57-2 11 45-7 17 0-3 S. 10-0 2 29-9 57-8 11 45-1 15 10-9 S. 9-9 3 29-9 56-9 11 38-3 15 9-7 S. 4-2 3 29-4 570 11 39-8 14 4-7 S. 3-9 4 29-4 56-9 11 42-9 14 3-1 N. 21 4 29-6 56-6 11 41-9 12 8-2 N. 2-2 5 30-6 56-5 12 3-8 12 10-1 N. 7-9 5 29-8 56-8 12 3-2 12 1-0 N. 7’6 6 33-5 56-7 12 39 0 12 10-7 N. 13-8 6 27-3 56-5 12 35-7 12 2-9 N. 13-5 7 28-9 56-8 13 1-9 13 9-5 N. 17-8 7 27-0 56-7 13 2-0 13 7-4 N. 17-9 8 29-3 56-9 13 8-5 15 4-1 N. 20-3 8 28-7 56-7 13 61 15 3-7 N. 20-6 9 31-2 57-2 12 59-9 16 1-6 N. 231 9 24 -2 57-6 12 59-8 16 5-1 N. 22-5 10 34-2 5 7-2 12 45-4 16 11-2 N. 22-5 10 25-6 57-3 12 46-5 17 4-7 N. 22-2 11 32-1 57-8 12 29-2 17 4-6 N. 21-5 11 30-7 57-5 12 30-0 17 7-1 N. 22-2 Upper Transits A, a.m. Lower (Interpolated) Transits A, p.m. ! 0 29-1 57-4 12 13-5 17 2-5 N. 18-5 0 32 1 57-4 12 11-2 18 2-1 N. 18-2 1 33-2 56-9 11 57-0 16 8-7 N. 14-9 1 29-4 57-6 11 57-3 17 8-5 N. 15-2 2 30-7 57-3 11 46-1 15 8-8 N. 10-1 2 29-5 57-2 11 45-5 16 6-4 N. 8-6 3 29-0 57-0 11 39-7 14 7-1 N. 3-7 3 30-5 571 11 37-3 15 4-5 N. 4-0 4 30-8 56-6 11 43-1 12 1 1-5 S. 2-5 4 29-8 56-9 11 42-8 13 10-9 N. 0-5 5 29-8 57-2 12 5-0 12 6-8 S. 7-8 5 29-6 56-8 12 3-0 12 7-9 S. 8-9 6 28-9 56-9 12 34-8 12 8-3 S. 13-4 6 31-0 56-7 12 35-6 12 5-4 S. 13-1 7 33-1 56-9 13 2-3 14 0-7 S. 18-2 7 23 3 57'2 13 0-4 13 8-5 S. 17-7 8 35-1 574 13 5-9 15 10-2 S. 20-9 8 24-8 5 7-2 13 8-5 14 10-5 S. 20-5 9 32-1 57-8 12 58-7 16 4-7 S. 22-4 9 31-9 57-3 12 58-9 15 10-1 S. 22-8 10 26-6 57-8 12 45-1 17 9*5 S. 22-7 10 34-1 57-9 12 42-8 17 1-5 S. 22-9 11 26-1 575 12 28-9 18 10 S. 22-1 11 34-2 58-2 12 26-9 17 10-6 S. 21-5 j February. Upper Transits A , P.M Lower (Interpolated) Transits A, a.m. 0 32-1 56-7 12 12-1 18 4-1 S. 9-9 0 30-9 57-9 12 12-1 17 11-2 S. 10-2 1 31-5 58-2 11 58-0 18 4-6 S. 3-8 1 30-8 57-1 11 57-9 16 9-8 S. 3-4 2 30-2 57-2 11 44-6 16 10-7 N. 2-3 2 28-9 57-3 11 46-3 15 7-8 N. 0-6 3 30-8 56-9 11 37-0 15 0-7 N. 8-6 3 27-7 57-3 11 36-2 14 2-8 N. 8-7 4 30' l 56-9 11 42-5 13 8-0 N. 13-4 4 28-8 56-8 11 41-5 12 8-8 N. 13-4 5 28’8 56-5 12 0-6 11 11-9 N. 18-1 5 29-8 56-6 12 3-9 II 9-0 N. 18-6 6 29-9 56-6 12 39-8 11 10-5 N.21-3 6 29-9 56-7 12 40-0 12 1-2 N. 2 TO 7 32-2 56-7 13 41 13 3-6 N. 22-6 7 26-7 56-7 13 3-3 13 9-8 N.21-9 8 34-1 57-2 13 5-6 15 1-2 N. 22-8 8 25-5 56-7 13 8-2 14 11-8 N. 23-2 9 32-8 57-1 12 577 16 6-2 N. 21-2 9 28-1 57-0 12 58-8 16 9-6 N. 21-6 10 31-4 57-4 12 42-8 17 8-9 N. 18-9 10 28-8 57-6 12 40-9 17 7-7 N. 18-8 11 29-4 56-9 12 26-2 17 10-8 N. 151 11 27-8 57-2 12 27-9 18 7-2 N. 15-2 Upper Transits A , A.M Lower (Interpolated) Transits A, p.m. 0 28-9 57-9 12 15-0 18 5-1 N. 9-8 0 33-3 57-1 12 12-6 18 5-9 N. 9-6 1 29-7 57-0 11 57-9 17 4-5 N. 3-3 1 31-0 57-8 11 56-8 18 0-9 N. 3-8 2 31-7 57-5 11 47-9 16 3-7 S. 2-3 2 28-7 56-9 11 49-6 16 8-3 S. 2-9 3 30-1 57-3 11 40-5 14 6-4 S. 7-5 3 27-5 571 11 39-6 15 0-4 S. 7-3 4 29-9 56-8 11 43-3 12 6*5 S. 13-4 4 28-7 57-3 11 41-5 13 0-9 S. 13-9 5 32-2 57-1 12 71 11 8-7 S. 18-9 5 27-4 57-4 12 3-4 11 7-8 S. 181 6 28-3 56-9 12 41-7 12 0-2 S. 20-8 6 27-9 56-7 12 40-9 11 8-9 S. 20-7 7 28-2 57-4 13 7-6 13 10-7 S. 22-3 7 30-3 57-3 13 6-1 13 4-4 S. 22-4 8 30-0 57-2 13 10-7 15 4-4 S. 23 -2 8 26-9 57-2 13 10-2 14 8-6 S. 22-6 9 32-6 56-9 13 0-0 16 7-7 S. 21-8 9 25-6 57-6 13 1-2 16 1-3 S. 22-3 10 33-2 57-7 12 45-3 18 2-9 S. 18-2 10 28-6 57-2 12 46-2 17 0-9 S. 19-6 11 30-7 57-9 12 28-5 18 9-4 S. 15-3 11 32-8 571 12 29-9 17 9-7 S. 14-1 MR. LUBBOCK ON THE TIDES Table VI. (/'.) (Continued.) | March. Upper Transits A, p.m. Lower (Interpolated) Transits A, a.m. S Apparent Moon’s Interval between Apparent Interval between the Moon’s Height of Moon’s the Moon’s Height of Parallax. 1 ransit and Tide. tion. Parallax. Transit and Tide. tion. i A* the Time of A. the Time of high water. high water. 1 h m / h m ft. in. h m h m ft. in. 1 0 307 57-8 12 12 3 18 10-4 N. 1-2 0 25-5 57-3 12 14-1 17 7-5 N. 1-2 | 1 31-0 57-2 11 58-3 17 5-1 N. 8-7 1 26-1 58-0 11 59-5 17 1-9 N. 6-7 2 29-9 57-6 11 46-0 16 4-6 N. 12-6 2 28-2 57-0 11 44-4 15 6-1 N.12-9 3 297 56-6 11 35-4 14 2-3 N. 17-4 3 29-9 56-9 11 36-4 13 9-3 N. 18-0 4 307 56-8 11 35-7 12 2-8 N. 20-9 4 28-6 56-7 11 41-0 12 1-9 N. 20-5 5 28-6 56-7 11 56-6 10 10-7 N. 22-8 5 29-3 56-6 12 1-6 11 1-7 N.21-9 6 31-8 56-5 12 42-5 11 6-8 N. 22-6 6 31-0 56-4 12 42-8 11 8-2 N. 22-6 7 297 56-6 13 5-9 13 1-4 N.21-4 7 32-2 56-6 13 6-9 13 4-6 N.21-9 8 28"5 56-6 13 9-2 14 10-1 N. 20-0 8 28-9 56-9 13 S-4 15 3-0 N. 19-4 9 317 56-9 12 57-8 16 6-2 N. 151 9 30-8 57-4 12 57-9 16 10-8 N. 15-4 10 29-5 57-6 12 43-5 17 10-8 N. 10-3 10 357 57’0 12 43-2 17 111 N. 10-2 11 29-4 57-2 12 29-9 18 1-0 N. 4-8 11 313 57-8 12 27 5 18 9-8 N. 4-8 Upper Transits A, a.m. Lower (Interpolated) Transits A, p.m. 0 317 58-1 12 12-2 18 3-9 S. 1-4 0 27-6 57-7 12 13-7 18 71 S. 0-6 1 28-9 57-8 11 58-7 17 3-9 S. 71 1 30-1 57-5 11 59-2 17 8-6 S. 8-3 2 31-9 57-3 11 45-2 15 11-4 S. 13-1 2 29-2 57-6 11 46-9 16 3-7 S. 12-7 3 35-0 57-3 11 346 14 1-1 S. 18-2 3 26-7 57-1 11 35-9 14 3-3 S. 17-4 4 307 56-9 11 37-2 12 5-8 S. 20-8 4 28-6 56-9 11 36-7 12 3-5 S. 20-8 5 30-5 567 12 2 1 11 6-8 S. 22-3 5 30-4 56-9 12 0-8 11 3-2 S. 22-2 6 32-4 56-8 12 44-4 12 1-9 S. 23-2 6 29-7 56-7 12 39-2 11 6-5 S. 22-9 7 31-2 57-1 13 5-2 13 8-7 S. 21-6 7 27-6 56-9 13 6-9 12 11-5 S. 21-9 8 32-5 56-8 13 7-9 15 4-8 S. 19-1 8 29-1 56-8 13 8-5 14 9-0 S. 20-1 9 27-6 57-6 12 58-9 17 2-2 S. 15-6 9 30-6 57-1 12 59-2 16 2-6 S. 14-9 10 29-0 57-3 12 427 18 20 S. 11-2 10 29-7 57-9 12 43-8 17 5-1 S. 10-3 11 30-9 58-0 12 27-4 19 1-1 S. 5-7 11 30-5 57-8 12 28-2 18 0-9 S. 5-7 April. Upper Transits A, p.m. Lower (Interpolated) Transits A, a.m. 0 29-5 57-6 12 14-3 17 9-7 N. 13-6 0 277 57-2 12 12-7 17 1-4 N. 11-9 i 1 307 57-0 11 58-3 13 7-2 N. 16-6 1 31-6 57-7 11 56-3 16 7-9 N. 17-0 2 327 57-5 11 43.2 15 4-3 M.20-7 2 30-3 57-2 11 42-7 15 2-8 N. 20-2 3 337 57-1 11 33-6 13 7-5 N. 22-6 3 27-6 57-0 11 33-4 13 9-4 N. 22-0 4 34-0 56-8 11 38-8 11 10-0 N. 22-7 4 28-6 56-6 11 36-7 12 3-2 N. 22-9 5 347 56-6 12 5-3 11 1-4 N. 22-0 5 28-1 57-0 12 0-9 11 6-3 N. 22-4 6 30-9 56-7 12 40-3 11 9-5 N.20-1 6 30-3 56-7 12 39-5 12 0-9 N. 19-0 7 32-6 56-8 13 2-8 13 9-4 N. 15-3 7 31-9 57-0 13 2-2 13 9-1 N. 16-1 8 31-9 57-0 13 5-3 15 6-7 N. 10-7 8 30-7 57-0 13 3-6 15 7-1 N.ll-7 9 26-6 57-3 12 58-4 16 11-6 N. 5-7 9 29-8 57-3 12 56-0 17 0-2 N. 5-1 10 27-5 57-1 12 42-9 17 8-6 S. 0-8 10 32-6 57’4 12 42-7 17 10-0 S. 0-5 11 26-6 57-9 12 29-6 18 3-6 S. 6-8 11 32-6 57-3 12 27 1 18 1-1 S. 7-4 Upper Transits A A.M Lower (Interpolated) Transits A, r.M. | 0 20-9 57-3 12 137 17 7-3 S. 11-5 0 33-0 58-0 12 11-3 17 10-3 S. 13-0 1 29-2 58-0 11 58-3 17 1-4 S. 17-4 1 28-8 58-0 11 58-0 16 10-5 S. 16-4 2 28-4 57-9 11 43-5 15 10-9 S. 20-6 2 31-4 57-6 11 43-2 15 1-7 S. 20-8 | 3 30-7 57-3 11 34-3 14 2-8 S. 21-9 3 31-1 57-3 11 35-3 13 8-5 S. 22-4 4 31-6 57-3 11 37-5 12 10-2 S. 23-4 4 28-8 57-3 11 37-7 12 2-2 S. 22-9 5 31-8 57-2 12 1-6 12 0-6 S. 22-1 5 27-8 57-2 12 1-0 11 2-6 S. 22-3 6 32-5 567 12 41-3 12 3-1 S. 19-6 6 27-3 56-8 12 37-5 11 6-0 S. 20-5 j 7 31-4 57-2 12 59-8 13 11-9 S. 157 7 25-4 57-3 13 1-3 13 2-3 S. 161 8 27-2 57-2 13 3-9 15 7-6 S. 11-9 8 28-4 57-2 13 5-0 15 0-7 S. 10-8 9 27-1 567 12 57-0 16 107 S. 6-0 9 30-4 57-4 12 56-4 16 5-1 S. 5-0 10 2(5-4 57-5 12 44 1 18 0-1 N. 0-6 10 29-4 57-0 12 44-4 .17 3-5 N. 0-5 11 28-3 ! 56-9 12 30-2 18 0-1 N. 6-7 11 29-7 57-6 12 29-5 17 9-5 N. 7-3 MR. LUBBOCK ON THE TIDES Table VI. (/.) (Continued.) May. ! Upper Transits A, p. m. Lower (Interpolated) Transits A, a.m. Apparent Solar Time of Moon’s Transit A. Moon’s Parallax. Interval between the Moon’s Transit and the Time of high water. Height of Tide. Moon’s Declina- tion. Apparent Solar Time of Moon’s Transit A. Moon’s Parallax. Interval between the Moon’s Transit and the Time of high water. Height of Tide. Moon’s Declina- tion. h m h m ft. in. h m / h m ft. in. 0 272 571 12 13-4 16 5-9 N. 20-9 0 29-9 57-4 12 129 17 0-3 N. 20-2 1 30-4 57T 11 57-6 15 9-9 N. 22-3 1 31T 571 11 56-0 16 3-2 N.21-8 2 31-4 57-5 11 43-2 14 10-7 N. 22-8 2 32-3 57 '2 11 41 -5 15 4-7 N. 23-3 3 29-4 57-0 11 35-7 13 7-9 N. 21-7 3 29-1 571 11 35-3 14 2-4 N. 21-9 4 2o-3 57-0 11 39-2 12 8-0 N. 20-6 4 30-7 56-9 11 38-1 13 3-3 N. 19-6 5 28-9 56-9 12 2-8 12 2-2 N. 15'9 5 28-9 56-9 12 1-9 12 7-6 N. 16-2 6 29-2 56-9 12 36-3 12 1T7 N. 11-5 6 27-7 57-0 12 33-6 13 T3 N. 12-5 7 26-9 57 '2 12 57-5 14 2-2 N. 5-4 7 29-9 57T 12 57 6 14 3T N. 5-9 8 2S-9 56'8 13 2-5 15 6-2 S. 0-8 8 29-6 57-4 13 0-8 15 5-8 N. 0-4 9 29-9 57'8 12 58-0 16 8-8 S. 6-9 9 29-5 57-2 12 55-0 16 4-6 S. 6-8 10 3T1 57-1 12 43-9 17 4-0 S. 1 T9 10 31-6 577 12 42-9 17 IT S. 12-2 11 32-5 57'2 12 28-2 17 8-7 S. 17-5 11 26-8 57T 12 30-9 17 4-8 S. 16-4 Upper Transits A A.M. Lowrer (Interpolated) Transits A, P.M. 0 29-3 57-8 12 12-2 17 3-9 S. 19-9 0 27-9 57-2 12 12-7 16 8-4 S. 20-3 1 27-3 57-5 11 56-6 16 8-1 S. 21-9 1 30-3 57-8 11 58-5 15 11-7 S. 22-5 2 28-8 57-7 11 43-1 15 9-6 S. 22-8 2 30-4 57-7 11 44-4 14 11-8 S. 22-6 ! 3 29-7 57-5 11 33-7 14 7-7 S. 22-6 3 28-8 57-7 11 38-2 13 8-5 S. 22 -2 4 31-0 57-3 11 38-9 13 75 S. 19-6 4 29-2 57-2 11 39-2 12 &*5 S. 20-3 5 30-4 57-4 12 3-4 12 10-7 S. 16-3 5 30-6 57T 12 4-9 11 9-4 S. 15-4 S 6 26-9 56-9 12 34-4 13 2-6 S. 12-2 6 31-5 57-4 12 38 1 12 4-4 S. 11-4 7 28-1 57-0 12 55-9 14 3-0 S. 5-9 7 33-6 57-4 12 57-4 13 9-7 S. 6-3 j 8 29-3 57-1 13 0-7 15 5-8 N. 0-5 8 31-9 56-9 13 1-7 15 0-0 N. 0-9 | 9 32-5 56-9 12 54-8 16 4-3 N. 6-9 9 29-9 5 7-2 13 56-5 16 6-2 N. 6-4 ! 10 34-1 57-1 12 40’3 16 7-0 N. 12-0 10 28-7 56-9 12 44-4 16 10-0 N. 11-8 11 30-1 57-0 12 29-7 17 0-5 N. 16-6 11 29-9 56-9 12 28-6 16 11-9 N. 17-0 | June. j Upper Transits A, p.m. Lower (Interpolated) Transits A, a.m. 0 30-8 57-4 12 121 16 3-7 N. 23-0 0 28-9 57T 12 11-5 16 11-5 N. 23-1 | 1 26-1 57-2 11 57-7 15 10-9 N. 221 1 32-6 57T 11 55T 16 5-7 N.21-6 | 2 29-4 56-8 11 43-4 14 10-9 N. 19-9 2 32-3 5 7-2 11 43-2 15 9-2 N. 18-8 3 31-7 56-8 11 37-6 13 10-9 N. 15-2 3 27-3 56-9 11 37-5 14 9-5 N. 16-4 1 4 30-9 571 11 45-0 13 2-3 N. 10-9 4 30-7 56-9 11 43-8 13 9-2 N.ll-4 5 29-4 58-7 12 5-0 12 6-9 N. 4-9 5 32-2 57-3 12 3-0 13 31 N. 4-9 6 29-5 57-0 12 37-5 13 1-8 S. 0-9 6 28-0 56-9 12 32-6 13 2-5 S. 0-8 7 31-8 57-2 12 57-8 14 1-7 S. 7-5 7 29-4 57-3 12 58-9 13 11-8 S. 7-2 8 33-3 57-4 13 2-2 15 6-9 S. 12-4 8 26-4 57 -6 13 T9 15 0-6 S. 11-9 9 34-9 57-7 12 56-9 16 7-8 S. 18-0 9 26-0 57-6 12 56-8 15 10-7 S. 16-4 | 10 28-6 57-9 12 45-3 17 3-0 S. 20-3 10 29-4 57-6 12 44 1 16 4-8 S. 20-5 11 26-6 57-4 12 30-5 17 4-3 S. 22-3 11 31-9 57*6 12 28-6 16 5-7 S. 22-4 Upper Transits A , A.M. Lower (Interpolated) Transits A, p.m. 0 25-3 57-3 12 10-9 17 3-0 S. 23-2 0 30-3 57-9 12 9-7 16 5-1 S. 22-9 1 27-3 57-8 11 57-0 16 10-7 S. 22-2 1 29-3 57-6 11 57-6 15 9-2 S. 22-5 2 27-4 57-6 11 44-1 16 4*o S. 19-5 2 28-5 57-4 11 44-8 15 0-5 S. 19-7 3 25-8 57-3 11 37-8 15 4-4 S. 16-7 3 31-9 57-3 11 38-8 13 11-3 S. 15-7 4 28-3 57-2 11 44-3 14 5-6 S. 10-3 4 32-7 57-4 11 45-3 13 0-4 S. 10-9 5 2 7-5 57-1 12 4-2 13 7-9 S. 5-8 5 29-9 56-9 12 6-0 12 41 S. 5-2 6 31-4 57-2 12 35-9 13 10-3 N. IT 6 31-7 56-9 12 35-6 12 8-8 N. TO 7 33-9 56-9 12 57-5 14 2-4 N. 7 0 7 28-5 57-3 12 56-4 13 9-7 N. 6-9 8 30-2 58-9 13 4-1 15 2-0 N. 12-3 8 29-5 57-0 13 2-3 15 0-0 N. 12-4 9 28-9 57-0 12 58-4 15 11-8 N. 16-4 9 32-7 57-4 12 55-9 16 4-4 N. 17-2 10 31-0 57-0 12 45-9 16 3-8 N. 20-6 10 30-1 57-9 12 44-9 16 9-9 N. 20-4 1 1 32-7 57-1 12 29-2 16 5-7 N. 22- 1 11 26-3 56-9 12 29-4 16 9-9 N.21-9 112 MR. LUBBOCK ON THE TIDES Table VI. (/.) (Continued.) July. Upper Transits A , P.M. Lower (Interpolated) Transits A, a.m. Apparent Solar Time of Moon’s Transit A. Moon’s Parallax. Interval between the Moon’s Transit and the Time of high water. Height of Tide. Moon’s Declina- tion. Apparent Solar Time of Moon’s Transit A. Moon’s Parallax. Interval between the Moon’s Transit and the Time of high water. Height of Tide. Moon’s Declina- tion. h m / h m ft. in. h m , h m ft. in. 0 34-5 56-9 12 13-2 16 10-2 N. 18-9 0 28-6 57-4 12 12-8 17 9-9 N. 19-7 1 34-5 57-2 11 58-2 16 5-5 N. 15-6 1 29-5 56-9 11 56-7 17 3-5 N. 16-5 2 31-3 57-0 11 44-0 15 6-7 N. 10-8 2 29-6 56-8 11 42-8 16 5-8 N. 10-9 3 30-4 56-6 11 41-4 14 4-8 N. 4-9 3 29-0 57-0 11 40-8 15 1-9 N. 5-0 4 30-8 56-9 11 45-3 13 4-5 S. 0-9 4 28-4 56-7 11 44-3 13 11-9 S. 0-7 5 28-8 56-7 12 5o 12 6-1 S. 7-6 5 30-5 57-0 12 5-3 13 0-6 S. 7-6 6 28-8 56-9 12 37-8 12 9-0 S. 13-2 6 30-9 57-2 12 35-1 12 10-1 S. 12-1 7 25-7 57-3 12 59-5 13 11-8 S. 17-4 7 31-9 57-2 13 0-7 13 7-4 S. 17-2 8 25-1 57-2 13 4-9 15 3-3 S. 20-0 8 34-1 57-2 13 6-8 14 7-7 S. 21-3 9 26-7 57-9 13 0-6 16 5-2 S. 22-6 9 31-0 57-7 12 59-3 15 9-6 S. 22-1 10 30-9 57-8 12 44-5 17 5-2 S. 22-9 10 2 6-2 57-9 12 46-7 16 3-5 S. 23-2 11 31-8 57-9 12 28-0 17 10-1 S. 21-5 11 26-9 58-1 12 30-8 16 11-3 S. 22-3 Upper Transits A A.M. Lower (Interpolated) Transits A, f.m. 0 25-7 57-8 12 14-5 17 11-8 S. 19-7 0 31-5 57-4 12 12-9 16 5-4 S. 19-3 1 25-4 57-2 11 59-2 17 4-2 S. 16-8 1 31-4 57-8 12 0-4 16 2-2 S. 15-6 2 29-2 57-4 11 48-4 16 8-4 S. 11-0 2 29-3 57 -2 11 45-7 15 5-6 S. 11-4 3 31-2 57-3 11 39-5 15 6-4 S. 4-9 3 32-4 56-9 11 44-7 14 2-3 S. 4-6 4 29-0 56-6 11 44-7 14 0-8 N. 1-7 4 31-2 57-2 11 47-5 13 1-0 N. 1-8 5 29-4 56-8 12 5-6 13 2-0 N. 6-2 5 27-4 56-7 12 4-4 12 1-6 N. 6-8 6 26-9 56-8 12 35-9 12 9-4 N. 12-7 6 29-6 56-7 12 38-8 12 3-7 N. 12-9 7 27-6 56-9 13 0-1 13 7-4 N. 17-0 7 33-1 571 13 3-1 13 9-3 N.17-1 8 29-5 57-1 13 6-7 14 8-2 N.20-7 8 34-1 56-8 13 6-6 15 0-6 N.21-0 9 28-3 57-3 13 2-6 15 9-7 N.21-9 9 32-6 57-3 12 57-9 16 3-9 N. 22-2 10 28-9 57-6 12 45-9 16 5-7 N.22-6 10 30-2 57-2 12 40-3 17 1-1 N.22-9 11 31(5 57-2 12 28-6 16 8-9 N.22-1 11 29-5 57-2 12 29-6 17 8-4 N.21-6 August. Upper Transits A, f.m. (Lower (Interpolated) Transits A, a.m. 0 31-7 57-5 12 14-1 17 6-7 N. 10-8 0 29-4 57-3 12 13-8 18 2-2 N. 10-6 1 31-4 57-3 11 59-7 16 10-6 N. 4-4 1 24-9 57-7 12 1-0 18 0-0 N. 5-6 2 28-2 57-3 11 46-1 16 2-6 S. 1-1 2 26-6 57-1 11 47-8 16 7-6 S. 0-7 3 26-2 56-7 11 41-4 14 7-7 S. 6-3 3 31-1 571 11 39-3 14 11-6 S. 6-4 4 27-4 56-9 11 42-5 13 1-8 S. 13-4 4 31-5 56-8 11 41-9 13 2-9 S. 12-1 5 24-5 56-7 12 1-0 12 0-1 S. 17-0 5 31-2 56-9 12 2-0 11 9-5 S. 18-2 6 24-9 56-7 12 37-3 12 2-7 S. 20-5 6 31-6 56-9 12 41-8 11 11-3 S. 20-7 7 26-3 57-2 13 4-3 13 9-4 S. 22-4 7 31-3 57-3 13 4-2 13 2-1 S. 22-5 8 28-8 56-9 13 9-3 15 2-8 S. 22-9 8 30-6 56-9 13 10-7 14 3-2 S. 22-8 9 29-0 57-6 13 1-6 16 11-6 S. 21-8 9 32-8 57-6 12 58-9 15 10-0 S. 22-1 10 2(5-6 57-8 12 46-8 18 0-9 S. 19-8 10 34-5 57-4 12 44-7 16 8-3 S. 18-9 11 26 -2 57-8 12 28-0 18 8-6 S. 15-7 11 35-3 58-2 12 28-2 17 5-5 S. 14-9 Upper Transits A, a.m. Lower (Interpolated) Transits A, f.m. 0 30-7 57-8 12 13-6 18 9-3 S. 10-5 0 25-8 58-1 12 15-7 17 5-6 S. 10-9 ] 29-3 58-0 11 59-4 18 4-0 S. 5-3 1 27-2 57-3 12 0-1 16 7-9 S. 5-2 2 28-6 56-9 11 46-7 16 9-0 N. 0-9 2 28-9 58-1 11 47-5 15 10-9 N. 1-3 3 28-9 571 11 40-2 15 3-7 N. 6-7 3 27-6 56-8 11 39-4 14 4-0 N. 6-4 4 26-9 56-9 11 41-2 13 4-1 N. 12-5 4 28-9 56-9 11 39-6 12 8-1 N. 13-4 5 28-4 56-5 12 2-8 11 9-3 N. 18-1 5 30-8 56-8 12 3-6 11 7-2 N. 16-7 6 28-6 56-5 12 41-2 11 11-7 N. 20-4 6 31-4 56-8 12 38-4 11 11-6 N. 20-8 7 24-9 56-6 13 4-9 12 11-9 N.21-8 7 33-6 56-6 13 6-2 13 6-9 N. 22-4 8 26-3 56-8 13 9-2 14 4*5 N. 22-9 8 32-3 56-9 13 9-3 15 2-1 N. 23-2 9 27-4 56-9 13 10 15 9-2 N.21-9 9 32 -2 56-7 12 59-5 16 6-2 N. 20-9 10 29-6 56-9 12 42-9 16 8-6 N. 19-5 10 31-0 57-4 12 45-0 17 8-5 N. 19-3 11 30-7 57-8 12 29-1 17 7-4 N.15 3 11 29-7 57-3 12 28-9 18 3-4 N.15-9 P/nl Trans . MLC '' XXXflll Plate [ p 116 Din (/ram showinq a comparison between the Calendar' Month. Inequality m the Interval and in the Hett/ht ofbujhwateras ilel need Iron/ BernoulHs 'Theory and from Observations at the London and Liverpool Docks See Tables IK ajzdXKUI. p.HS and /9?. INTERVAL INTERVAL HEIGHT HEIGHT ( ... .. ....... London 19 Years ( 13.970 Observation s ) Theory Observation •< .....i 35 Yea/v (?•/., we Observations ) I Liverpool 29 Years ( 13.391 Observations ) In this comparison of the London and Liverpool results, the London corrections have been shifted to the left half an hour *<5 <6 N05^9ji“05j,»l%f3!t530l5 05 tv tv tv *S *>• *S lv tv tv M r'1 ’S ^ ^ F 1 g" 1 . I I 1 Mean Height 1/37 n Diagram showing the E stablishinent of the Port of London See Table XXX . p. 136. Mean Interval ^r^rvir^rvj^rvj^^o^^^.es, rv 1630 1832 1834 -i ■ 1 1 Lj „1_L 1 1 i i i i i i i i 1 ■ 1 ■ 1 i 1 . ,1,1 Fig.2. b:z. A.v / \ / *"■■■ — _L : — L ■■■■■■ .zzz;. b :b_~ :::. : A —-zb — / ' • \ /-■ V i rrS H& t 3- LI Mean Height 22 36 Diagram showing die errors of calculated Heights of -r-r ’ ° Highly a±err for Mag & Jiaie and die corresponding Heights of the B ammeter at Liverpool Se London See. p.104. M a J u n e iig| g\ g\ w. |a 1 3 5 7 \9\ \n |Z3 g \17\ |zg| I 21 |aa[ \25\ \27\ lgg| 31 2 4 ' 6 8 1 10 22 24 \W\ 28\ So — ! brb: Observed H eight o£ High Wat Fig. 3 . eT minus Caleul 0 I ated Height 'V\ bL TH \ /r v 'vy--/ \ ■/'"b ,b s ?! ' ' vV£'A" A i - f \ i ■ -FP— SEEF /[ A r ■Cl Height of B aiometer \ V rj f K _ 2 t- \ ■. > / v‘ ...\ ... k \\, ; f \; /• 1 pp' 1 Uf, v v\ I 1 V- Liverpool. London MR. LUBBOCK ON THE TIDES 121 Table XII. (/.) Showing the Interval and Height of High Water at the Liverpool Docks, with the Sun s and Moon s Declinations, and the Moon’s Horizontal Parallax (for the mean of all the Moon s I lansits A occurring between 01' and D) for every year from 1774 to 1792. Year. Number of Obser- vations. Moon’s Transit A. 1774 58 h m 0 27-5 1775 57 0 29-3 1776 59 0 30-8 1777 59 0 32-2 1778 52 0 30-6 1779 58 0 29-3 1780 62 0 29-3 1781 59 0 29-5 1782 53 0 29-6 1783 57 0 30-3 1784 59 0 29-4 1785 55 0 31-3 1786 62 0 29-6 1787 62 0 28-3 1788 55 0 30-0 1789 54 0 28-1 1790 56 0 28-2 1791 55 0 29-6 1792 62 0 29-3 Interval. Height. h m ft. in. 12 15-4 18 0-9 12 14-3 17 10-7 12 12-3 17 11-7 12 121 17 10-1 12 121 17 100 12 1-2-7 17 8-9 12 11-9 17 6-7 12 11-9 17 60 12 10-5 17 4.4 12 11-6 17 4.7 12 12-5 17 2-0 12 11-4 17 41 12 11-3 17 3-1 12 13-1 17 7-0 12 119 17 5-8 12 13-7 17 111 12 14-8 17 9-8 12 14-8 18 3-8 12 15-4 18 10 Moon’s Declina- tion. Moon’s Hor. Par. Sun’s Declina- tion. 0 10-9 57-6 140 11-6 57-4 140 12-7 57-3 14-5 140 57-3 14-6 15-1 57-4 14-6 15-8 57-6 14-4 16-8 57-3 14-4 16-9 57-3 14-2 17-2 57-4 13-6 16-8 57-7 13-7 17-3 57-3 141 16-5 57-4 14-3 161 57-3 14-4 151 57-6 141 14-0 57-4 14-7 12-4 57-4 140 11-9 57-3 14-4 11-7 57-6 14-9 11-2 57-3 14-4 Table XIII. (m.) Interpolated from Table XII. by re- ducing each quantity to Moon’s Transit A (0h30m),and correcting the quantities for deviation from mean Declinations and Parallax. Moon’s Transit A = 0h 30m. Year. Interval. Height. 1774 h ra feet. 12 14-7 17-40 1775 12 141 17-46 1776 12 12-5 17-65 1777 12 12-7 17-65 1778 12 12-3 17-67 1779 12 12-5 17-53 1780 12 11-7 17-55 1781 12 11-8 17-49 1782 12 10-4 17-34 1783 12 11-7 17-20 1784 12 12-3 17-19 1785 12 110 17-27 1786 12 11-2 17-20 1787 12 12-9 17-32 1788 12 11-9 17-24 1789 12 13-2 17-55 1790 12 14-3 17-45 1791 12 14-7 17-84 1792 12 15-2 17-69 i - - Table XIV. ( n .) Showing the Establishment of the Port of Liverpool obtained from Table XIII. by altering the argu- ment from Transit A to Transit D, and reducing it to 0h 0m from 0h 30m. Moon’sHor. Par. 57', andDecl. 1 5°. Moon’s Transit D = 0h 0m. Year. Interval.* Height. h m feet. 1774 11 28-3 17-31 1775 11 27-7 17-37 1776 11 26-1 17-56 1777 11 26-3 17-56 1778 11 25-9 17-58 1779 11 261 17-44 1780 11 25-3 17-46 1781 11 25-4 17-40 1782 11 24-0 17-25 1783 11 25-3 1711 1784 11 25-9 17-10 1785 11 24-6 17-18 1786 11 24-8 17-11 1787 11 26-5 17-23 1788 11 25-5 17-15 1789 11 26-8 17-46 1790 11 27-9 17-36 1791 11 28-3 17-75 1792 11 28-8 17-60 * i. e. Establishment . MDCCCXXXVII. R 122 MR. LUBBOCK ON THE TIDES Results deduced from Observations made at LONDON. Table XV. (a.) Showing the Interval between the Apparent Solar Time of the Moon’s Transit and the Time of High Water, and the Height of High Water at the London Docks, corresponding to the Apparent Solar Time of the Moon’s Transit B in each month of the year, from 24,592 observations made at the London Docks, between the 1st of September 1801 and the 31st of August 1836. January. February. Number of Obser- vations. Apparent, Solar Time of Moon’s Transit B. Interval between the Moon’s Transit and the Time of high water. Height of Tide. Mean of Moon’s Declina- tion. Mean Horizontal Parallax. Number of Obser- vations. Apparent Solar Time of Moon’s Transit B. Interval between the Moon’s Transit and the Time of high water. Height of Tide. Mean of Moon’s Declina- tion. Mean Horizontal Parallax. h m h m ft. in. h m h m ft. in. / 167 0 30-1 3 3-9 22 91 19 57-1 165 0 30-2 3 5-5 22 10-8 10 57-3 166 1 29-7 2 49-7 22 6-3 15 57-3 169 1 28-3 2 50-9 22 8-2 6 57-2 186 2 29 1 2 38-1 21 11-4 10 57-1 172 2 28-4 2 38-5 22 1-4 5 57-2 188 3 29-6 2 30-5 21 4-8 6 56-9 175 3 29 1 2 27 1 21 3-8 8 56-9 189 4 29-9 2 28-9 20 60 5 56-9 166 4 29-9 2 22-9 20 0-9 14 56-7 194 5 30-1 2 41-7 19 7-3 9 56-9 152 5 29-6 2 32-5 19 2-2 18 56-6 179 6 29-3 3 9-4 19 7-0 13 56-9 151 6 29-7 3 9-6 19 1-5 21 56-7 176 7 29-3 3 40-7 20 1-8 18 57-0 144 7 29-0 3 43-8 19 11-2 22 56-8 169 8 29-9 3 52-8 20 11-9 21 57-2 142 8 28-7 3 56-9 20 9-4 23 56-9 154 9 29-2 3 50-7 21 8-9 22 57-2 149 9 28-6 3 511 21 6-7 21 57-1 162 10 29-1 3 37-8 22 3-2 23 57-2 157 10 30-0 3 37-2 22 41 19 5 7-2 158 11 291 3 19-9 22 7-4 21 57-2 157 11 30-8 3 20-6 22 9 *5 15 57-3 Sun’s Declination 21 0( Sun’s Declination 13°. March. April. 178 0 29-3 3 7-8 22 10-8 5 57-2 170 0 29 0 3 90 23 0-0 12 57-3 185 1 29-9 2 50-5 22 8-2 8 57-1 165 1 28-9 2 51-8 22 5-8 17 57-2 176 2 29-6 2 35-1 22 00 13 56-9 161 2 29-0 2 34-7 21 10-5 20 57-0 170 3 28-7 2 21-6 20 11-8 17 56-8 154 3 29-2 2 21-0 20 11-2 22 56-8 167 4 28-8 2 16-7 19 9-9 20 56-7 155 4 29 1 2 15-4 19 10-4 23 56-7 166 5 30-0 2 28-4 18 10-8 22 56-7 157 5 29-0 2 31-4 19 1-6 22 56-5 163 6 29-6 3 9-5 19 0-4 23 56-8 165 6 28-8 3 9-6 19 2-9 20 56-7 163 7 28-9 3 47-4 19 10-0 22 56-9 174 7 29-2 3 43-5 20 1-9 16 56-7 177 8 29-0 3 58-3 20 11-8 19 57-2 175 8 29-2 3 54-5 21 3-3 11 57-0 175 9 29-6 3 50-5 21 10-7 16 57-3 186 9 30 0 3 49-8 22 21 6 57-2 180 10 30-3 3 36-7 22 6-6 11 57-4 175 10 29-1 3 39-5 22 9-4 5 57-3 187 11 30-5 3 23-7 22 11-2 6 57-5 179 11 28-9 3 23-0 23 1-4 7 57-4 Sun’s Declination 3°. Sun’s Declination 10°. May. June. 166 0 30-0 3 6-9 22 10-3 20 57-6 157 0 28-2 3 5-8 22 6-8 23 57-3 161 1 29-8 2 51-6 22 5-6 22 57-5 156 1 29-3 2 51-2 22 3-8 22 57-4 165 2 30-0 2 34-5 21 8-1 23 57-2 163 2 29-5 2 38-1 21 10-6 19 57-3 163 3 30-1 2 22-5 20 10-4 22 56-9 172 3 30 0 2 28-7 21 2-9 16 57-0 170 4 29-7 2 21-8 20 1-3 20 56-8 176 4 30-0 2 30-6 20 7-2 11 56-8 171 5 29-4 2 37-5 19 8-2 16 56-6 186 5 29-6 2 45-0 20 0-9 7 56-7 183 6 29-4 3 120 19 9-7 12 56-5 184 6 29-8 3 12-0 19 11-9 5 56-6 192 7 29-7 3 39-3 20 6-7 7 56 -7 179 7 29-3 3 37-5 20 7-2 7 56-8 188 8 29-8 3 50-6 21 5-0 5 56-8 179 8 29-4 3 47-7 21 2-5 12 56-9 183 9 30-0 3 49-3 22 2-0 7 570 161 9 29-0 3 47-6 21 10-0 17 57-0 176 10 29-2 3 39-0 22 8-0 12 57 -2 161 10 29-3 3 36-4 22 3*4 20 57-1 175 11 28-9 3 24 '4 22 9-9 17 57-3 149 11 28-8 3 22-4 22 6-6 22 57 -2 Sun’s Declination 19°. Sun’s Declination 23°. MR. LUBBOCK ON THE TIDES 123 Table XV. (a.) (Continued.) July. August. Number of Obser- vations. Apparent Solar Time of Moon’s Transit B. Interval between the Moon’s Transit and the Time of high water. Height of Tide. Mean of Moon’s Declina- tion. Mean Horizontal Parallax, Number of Obser- vations. Apparent Solar Time of Moon’s Transit B. Interval between the Moon’s Transit and the Time of high water. Height of Tide. Mean of Moon’s Declina- tion. Mean Horizontal Parallax. h m h m in. h m h m ft. in. 159 0 30-0 3 6-6 22 7-4 19 57-2 179 0 30-6 3 100 22 10-3 ii 57-0 167 1 28-4 2 52-7 22 6-3 16 57-1 178 1 29-7 2 53-4 22 7-9 6 56-9 186 2 29-7 2 40-7 22 21 11 57-1 181 2 28-8 2 42-0 22 1-6 5 57-0 186 3 29-7 2 34-7 21 6-0 6 571 184 3 29-0 2 31-2 21 4-4 8 56-9 198 4 29-3 2 33-4 20 8-7 5 56-9 182 4 29-4 2 27-5 20 5*4 13 56-7 191 5 29-3 2 46-6 20 1-0 8 56-9 174 5 29-0 2 38-5 19 6-4 17 56-7 185 6 29-0 3 14-4 19 10-4 13 56-8 175 6 29-2 3 11-7 19 4-4 20 56-9 175 7 29-2 3 39-2 20 4-0 17 56-9 168 7 30-2 3 43-8 20 0-2 22 57-0 165 8 29-0 3 52-3 21 0-4 20 56-9 162 8 30-0 3 57-7 20 11-2 23 57-1 162 9 29-2 3 50-6 21 8-5 22 571 165 9 29-9 3 53-7 21 8-4 22 572 154 10 29-6 3 39-5 22 2-8 23 57-1 165 10 30-0 3 40-6 22 3-6 19 57-3 164 11 30-5 3 22-3 22 5-6 22 57-2 171 11 29-8 3 28-2 22 8-5 16 57-3 Sun’s Declination 21°. Sun’s Declination 14°. September. October. 179 0 29-4 3 10-9 22 11-9 4 57-4 175 0 30-0 3 10-6 22 111 12 57-5 182 1 29-7 2 54-0 22 7-4 7 571 173 1 29-7 2 53-0 22 6-4 16 57-4 173 2 29-8 2 38-3 22 0-9 12 57-0 166 2 29-8 2 34-9 21 10-3 20 57-0 163 3 29-0 2 27-3 21 0-9 17 56-9 164 3 28-9 2 21-3 20 10-5 22 56-9 164 4 29-3 2 17-5 19 11-4 20 56-7 157 4 28-9 2 12-5 19 iO-8 23 56-8 157 5 30-0 2 28-8 19 1-7 22 56-7 164 5 29-2 2 24-8 19 0-8 22 56-6 155 6 29-9 3 11-6 18 11-5 23 56-7 170 6 30-6 3 5-6 19 10 20 56-6 160 7 29-1 3 47-7 19 10-8 22 56-8 167 7 30-6 3 44-6 20 1-2 17 56-6 164 8 28-4 3 59-7 20 11-5 20 57-0 180 8 29-7 3 56-5 21 2-5 12 56-9 174 9 29-5 3 54-5 21 10-5 16 57-2 187 9 28-7 3 52-3 22 1-0 7 571 176 10 30-1 3”44-l 22 6-7 12 57-3 190 10 29-0 3 41-4 22 8-9 5 57-4 177 11 29-8 3"2 7-7 22 111 6 57-4 189 11 30-1 3 26-8 22 11-3 7 57-5 Sun’s Declination 4e. Sun’s Declination 9°. November. December. 162 0 28-9 3 7-3 22 6-8 20 57-4 157 0 29-4 3 4-6 22 6-2 22 57-3 158 1 28-9 2 49-2 22 3-2 22 57-4 159 1 29-6 2 47-6 22 2-8 22 57-3 152 2 29-2 2 33-2 21 9-4 23 57-3 165 2 30-0 2 33-4 21 111 20 57-2 163 3 29-3 2 23-4 21 0-6 22 57-2 175 3 30-4 2 27 9 21 1-7 16 57-1 j 161 4 29-4 2 18-8 20 0-6 20 56-8 185 4 29-7 2 26-7 20 5-6 11 56-9 ! 169 5 28-7 2 32 -2 19 6-6 17 56-6 197 5 29-8 2 38-9 19 10-6 7 56-9 j 185 6 30-0 3 70 19 6-0 12 56-7 181 6 29-2 3 8-2 19 10-2 5 56-7 177 7 30-2 3 37 4 20 4-8 7 56-8 193 7 28-4 3 34-3 20 5-2 8 56-7 182 8 29-9 3 50-6 21 3-6 5 56-8 184 8 29-2 3 46-4 21 3-3 12 56-9 174 9 29-4 3 46-8 22 0-9 7 571 167 9 29-3 3 47-6 21 10-7 17 571 176 10 29-6 3 37-9 22 5-0 11 57-2 160 10 28-6 3 36-9 22 3-5 20 57-2 159 11 29-3 3 23-6 22 9-5 16 57-3 163 11 28-5 3 21-5 22 5-1 22 57-2 Sun’s Declination 18°. Sun’s Declination 23 O Table XVI. (b.) (Interpolated from Table XV.) Showing the Interval between the Apparent Solar Time of the Moon’s Transit B, and the Time of High Water at the London Docks for each month in the year. Apparent Solar Time of Moon’s Transit B. January. February. March. April. May. June. July. August. Sept. October. Nov. Dec. Mean. h m h m h m h m h m h m h m h m h m h m h m h m h m h m 0 30 3 3-8 3 5-3 3 7-5 3 8-5 3 6-6 3 5-1 3 6-5 3 10-2 3 10-5 3 10-3 3 6-8 3 4-2 3 7-1 1 30 2 49-3 2 50-3 2 50-4 2 51-4 2 511 2 50-6 2 52-2 2 53-4 2 53-8 2 52-5 2 48-5 2 47-2 2 50-9 2 30 2 37-7 2 37-8 2 35-2 2 34-5 2 34-1 2 37-4 2 40-6 2 41-8 2 38-3 2 34-9 2 32-5 2 33-0 2 36-5 3 30 2 30-9 2 27-5 2 22-3 2 21-7 2 22-9 2 28-7 2 34-3 2 31-6 2 27-7 2 21-7 2 227 2 27-5 2 267 4 30 2 29-3 2 24-2 2 18-2 2 16-9 2 22-8 2 31-5 2 33-9 2 28-9 2 18-9 2 13-6 2 19-8 2 27-2 2 23-8 5 30 2 42-1 2 34-4 2 29-7 2 34-0 2 39-5 2 46-5 2 47-4 2 40-3 2 30-1 2 26-9 2 34-6 2 39-4 2 37-1 6 30 3 100 3 10-3 3 10-0 3 10-7 3 13-1 3 12-8 3 15-2 3 12-3 3 12-2 3 6'0 3 7-5 3 9-1 3 10-8 7 30 3 40-7 3 43-9 3 47-5 3 43-4 3 39-2 3 37-5 3 39-3 3 43-8 3 47-8 3 44-1 3 37-3 3 34-4 3 417 8 30 3 53-1 3 56-8 3 58-6 3 54-5 3 50-3 3 47-6 3 52-2 3 57-8 o •> 59'6 3 56-4 3 50-3 3 46-3 3 53-6 9 30 3 50-9 3 50-9 3 50-8 3 50- 1 3 49-3 3 47-4 3 50-6 3 54-0 3 54-7 3 52-2 3 46-8 3 47-6 3 50-4 10 30 3 37-8 3 374 3 371 3 39-5 3 39-0 3 36-3 3 39-5 3 40-8 3 44-3 3 41-5 3 38-0 3 36-8 3 39-0 11 30 3 19-7 3 20-8 3 23-8 3 22-7 3 24-1 3 22- 1 3 22-4 3 28-1 3 27-6 3 26-8 3 23-4 3 21-1 3 23-6 124 MR. LUBBOCK ON THE TIDES Table XVII. (c.) (Interpolated from Table XV.) Showing1 the Height of High Water at the London Docks, corresponding to the Apparent Solar Time of the Moon’s Transit B, in each month of the year. Apparent Solar Time of Moon’s Transit B. January. February. March. April. May. June. July. August. Sept. October. Nov. Dec. Mean. h m feet. feet. feet. feet. feet. feet. feet. feet. feet. feet. feet. feet. feet. 0 30 22-74 22-84 22-86 22-94 22-75 22-50 22-58 22-86 22-91 22-82 22-49 22-46 22-73 1 30 22-45 22-62 22-66 22-43 22-37 22-23 22-48 22-68 22-60 22-45 22-17 22-15 22-44 2 30 21-91 22-05 22-01 21-85 21-63 21-80 22-16 22-11 22-07 21-86 21-69 21-88 21-92 3 30 21-42 21-33 21-00 20-96 20-90 21-24 21-46 21-37 21-08 20-87 20-98 21-12 21-14 4 30 20-53 20-16 19-87 19-93 20-16 20-66 20-74 20-52 20-02 19-94 20-10 20-49 20-22 5 30 19-64 19-30 18-99 19-27 19-80 20-16 20-10 19-61 19-23 19-18 19-66 19-91 19-55 6 30 19-61 19-20 19-07 19-31 19-94 20-09 19-92 19-40 19-03 19-17 19-57 19-93 19-52 7 30 20-17 19-99 19-87 20-25 20-64 20-65 20-37 20-02 19-96 20-18 20-44 20-55 20-26 8 30 20-95 20-83 20-97 21-29 21-46 21-24 21-08 20-91 21-00 21-24 21-34 21-31 21-14 9 30 21-72 21-57 21-84 22-13 22-17 21-85 21-71 21-66 21-84 22-09 22-06 21-89 21-89 10 30 22-24 22-30 22-47 22-73 22-64 22-27 22-22 22-24 22-50 22-67 22-38 22-27 22-42 11 30 22-59 22-74 22-84 23-05 22-77 22-55 22-44 22-66 22-85 22-85 22-74 22-40 22-71 In reducing the above Tables from Table XV., the quantities have been corrected for the deviation from a mean Horizontal Parallax (57'). Table XVIII. (d.) Showing the Interval between the Apparent Solar Time of the Moon’s Transit and the Time of High Water at the London Docks, corresponding to the Apparent Solar Time of the Moon’s Transit B, for every minute of her Horizontal Parallax. Hor. Par. 54'. Hor. Par. 55'. Number of Obser- vations. Apparent Solar Time of Moon’s Transit B. Interval between the Moon’s Transit and the Time of high water. Height of Tide. Moon’s Declina- tion. Sun’s Declina- tion. Number of Obser- vations. Apparent Solar Time of Moon’s Transit B. Interval between the Moon’s Transit and the Time of high water. Height of Tide. Moon’s Declina- tion. Sun’s Declina- tion. h m h m in. h m h m ft. in. 409 0 29-2 3 6-2 22 2-7 14-5 14-3 280 0 30-3 3 6-5 22 3-4 14-4 14-5 417 1 29-3 2 48-3 21 10-2 14-5 14-3 289 1 29-2 2 48-9 22 1-4 14-4 14-9 383 2 29-0 2 30-7 21 4-0 14-9 14-7 322 2 29-9 3 32-3 21 6-3 14-0 14-5 375 3 28-9 2 14-5 20 5-8 14-7 15-0 343 3 29-2 2 19-1 20 7-8 14-8 15-0 331 4 29-2 2 10-7 19 6-9 14-9 14-9 385 4 30-0 2 15-0 19 8-0 14-8 15-0 293 5 28-9 2 25-4 18 8-4 15-5 14-9 412 5 301 2 29-2 18 11-3 14-9 15-2 298 6 30-0 3 7-3 18 8-7 15-0 15-3 412 6 28-9 3 60 18 11-1 15-0 15-2 334 7 30-6 3 42-9 19 4-2 15-1 15-5 385 7 29-3 3 42-6 19 8-6 14-9 14-7 364 8 29-6 3 57-5 20 5-7 14-8 14-9 347 8 29-6 3 55-7 20 8-9 14-4 15-1 402 9 29-3 3 54-3 21 3-8 14-7 14-8 293 9 29-1 3 53-5 21 5-3 14-6 14-3 406 10 29-3 3 41-5 21 11-0 14-3 14-4 294 10 30-1 3 42-1 21 11-9 14-5 14-3 410 11 29-8 3 24-8 22 2-4 14-1 14-2 290 11 29-8 3 24-6 22 3-9 14-2 14-3 Hor. Par. 56'. Hor. Par. 57'. 219 0 29-2 3 5-9 22 7-0 14-3 14-2 166 0 30-0 3 6-2 22 8-4 14-5 14-3 203 1 29-5 2 49-5 22 3-0 14-2 14-3 182 1 30-1 2 51-5 22 4-8 14-9 14-4 228 2 29-0 2 35-3 21 8-5 14-6 151 201 2 30-2 2 36-6 21 10-8 14-9 14-6 234 3 30-2 2 24-9 20 10-4 14-8 14-9 215 3 29-9 2 27-2 21 2-9 14-7 14-3 259 4 29-4 2 19-7 20 0-5 14-9 151 233 4 29-9 2 24-0 20 3-6 15-0 15-2 276 5 29-4 2 32-9 19 4-2 14-7 15-2 256 5 29 -2 2 37-2 19 8-3 15-5 150 271 6 29-8 3 8-0 19 3-3 14-8 15-4 254 6 29-4 3 8-8 19 6-3 15-0 15-3 253 7 28-8 3 41-4 20 0-3 14-7 14-9 240 7 28-6 3 42-0 20 2-7 15-1 15-2 254 8 28-7 3 56-3 20 10-5 15-1 14-5 210 8 29-1 3 52-8 21 1-5 15-0 14-5 226 9 29-0 3 52-3 21 7-6 14-7 14-6 202 9 29-0 3 51-3 21 10-2 14-8 14-5 217 10 28-5 3 40-1 22 2-9 14-5 14-5 187 10 27-7 3 39-0 22 3-0 14-7 14-9 206 11 29-0 3 25-3 22 5-8 14-6 14-7 182 11 30-0 3 21-7 22 9-0 14-0 140 MR. LUBBOCK ON THE TIDES 125 Table XVIII. ( d .) (Continued.) Hor. Par. 58'. Hor. Par. 59'. Number of Obser- vations. Apparent Solar Time of Moon’s Transit B. Interval between the Moon’s Transit and the Time of high water. Height of Tide. Moon’s Declina- tion. Sun’s Declina- tion. Number of Obser- vations. Apparent Solar Time of Moon’s Transit B. Interval between the Moon’s Transit and the Time of high water. Height of Tide. Moon’s Declina- tion. Sun’s Declina- tion. h m h m ft. in. h m h m ft. in. 158 0 31-1 3 8-0 22 9-9 14-6 14-5 180 0 28-2 3 9-4 23 0-8 14-2 14-3 173 1 29-1 2 51-5 22 7-9 14-5 14-2 182 1 300 2 52-4 22 10-0 14-1 14-4 197 2 29-7 2 39-7 22 1-3 14-7 14-9 204 2 30-4 2 40-1 22 4-5 14-7 14-8 208 3 29-6 2 32 0 21 4-8 15-0 14-4 282 3 310 2 34-3 21 7-8 14-8 14-4 268 4 28-9 2 28-3 20 5-9 14-8 151 404 4 32-3 2 33-6 20 10-0 14-9 14-6 288 5 29-9 2 41-7 19 11-0 14-9 14-8 533 5 30-0 2 44-1 20 3-5 15-0 15-1 290 6 28-5 3 11-7 19 8-8 15-4 14-9 518 6 29-6 3 14-2 20 1-5 151 15-0 254 7 28-1 3 40-2 20 6-2 14-6 15-0 381 7 27-6 3 38-6 20 8-6 14-7 15-0 220 8 27-9 3 53 0 21 3-2 15-3 14-7 258 8 27-8 3 49-3 21 6-9 14-2 14-7 184 9 28-3 3 49-4 22 1-7 14-9 14-8 216 9 28-6 3 48-4 22 2-5 14-6 14-2 171 10 30-0 3 38-1 22 6-9 14-7 14-5 176 10 29-7 3 37-5 22 10-0 14-2 14-2 174 11 29-4 3 23-7 22 10-0 14-7 14-7 164 11 28-0 3 24-6 23 0-4 14-4 14-4 Hor. Par. 60'. Hor. Par. 61 200 0 29-3 3 7-4 23 4-2 14-9 14-8 390 0 29-7 3 8-0 23 5-8 14-3 14-5 223 1 30-5 2 53-7 23 0-7 14-4 14-3 301 1 28-4 2 55-0 23 3-4 14-6 14-5 327 2 31-5 2 42-4 22 7-2 14-3 14-2 172 2 22-8 2 44-2 22 90 15-1 15-5 380 3 28-1 2 35-7 21 11-9 14-5 15-0 10 3 13-7 3 14-2 21 9-3 16-6 15-7 180 4 22 7 2 35-4 21 2-0 15-2 15-6 12 5 7-6 2 50-2 20 4-5 17-2 16-2 28 6 42-7 3 25-4 20 2-9 16-4 14-2 207 7 35-0 3 41-0 21 0-1 15-1 15-5 388 8 31-1 3 49-0 21 9-0 15-5 15-9 18 8 47-2 3 52-4 21 10-2 16-7 17-9 309 9 26-8 3 46-3 22 5-7 140 13-8 195 9 36-4 3 44-7 22 8-8 15-3 15-5 229 10 28-2 3 37-0 22 11-6 14-4 14-2 342 10 31-2 3 36-2 23 2-0 14-3 14-6 203 11 28-7 3 22-7 23 3-4 140 14-0 386 11 30-1 3 22-8 23 4-7 14-3 14-3 Table XIX. ( e .) (Interpolated from Table XVIII.) Apparent Solar Time H. P . 54'. H. P. 55'. H. P. 56'. H. P. 57'. of Moon’s Transit Height of Height of Interval. Height of Interval. Height of B. Tide. Tide. Tide. Tide. h m h m feet. h m feet. h m feet. h m feet. 0 30 3 6-1 22-22 3 6-4 22-26 3 5-7 22-55 3 6-2 22-68 1 30 2 48-2 21-83 2 48-7 22-06 2 49-4 22-21 2 51-6 22-40 2 30 2 30-5 21-31 2 3 2-2 21-52 2 35-0 21-67 2 36-7 21-90 3 30 2 14-5 20-44 2 19-1 20-62 2 24-9 20-86 2 27-4 21-23 4 30 2 10-9 19-52 2 15-0 19-74 2 19-6 20-03 2 23-9 20-30 5 30 2 26-2 18-69 2 29-0 18-94 2 32-9 19-34 2 37-9 19-66 6 30 3 7-3 18-72 3 6-5 18-94 3 8-1 19-26 3 9-1 19-51 7 30 3 42-8 19-34 3 42-7 19-73 3 41-7 20-03 3 42-3 20-23 8 30 3 57-5 20-47 3 56 0 20-73 3 56-0 20-90 3 52-5 21-14 9 30 3 54-2 21-32 3 53-4 21-44 3 52-1 21-64 3 51-0 21-84 10 30 3 41-3 21-90 3 42-1 21-98 3 39-7 22-24 3 39-2 22-27 11 30 3 24-8 22-16 3 24-6 22-29 3 25 0 22-46 3 21-7 22-71 H. P. 58'. H. P. 59'. H. P. 6(y. H. P. 61'. 0 30 3 8-3 22-80 3 8-9 23-03 3 7-2 23-35 3 7-9 23-47 1 30 2 51-3 22-63 2 52-4 22-79 2 53-8 23-05 2 54-6 23-24 2 30 2 39-6 22-09 2 40-2 22-37 2 42-7 22-60 2 42-8 22-61 3 30 2 32-2 21-39 2 34-5 21-62 2 35-4 21-92 4 30 2 28-4 20-46 2 33-3 20-88 2 36-7 2100 5 30 2 41-7 19-92 2 44-1 20-29 6 30 3 12-5 19-77 3 14-4 20-12 7 30 3 40-8 20-54 3 39-3 20-76 3 40-0 20-92 8 30 3 52-6 21-33 3 49-4 21-60 3 49-2 21-74 9 30 3 49-1 22-17 3 48-1 22-18 3 45-6 22-45 3 45-9 22-61 10 30 3 38-0 22-56 3 37-4 22-80 3 36-6 22-97 3 36-6 23-13 11 30 3 23-5 22-82 3 24-1 23-02 3 22-4 23-24 3 22-8 23-34 In forming the above Table, the quantities have been corrected for deviations from mean Declinations. 126 MR. LUBBOCK ON THE TIDES Table XX. (/.) Showing the Interval between the Apparent Solar Time of the Moon’s Transit and the Time of High Water, and the Height of High Water at the London Docks, corresponding to the Apparent Solar Time of the Moon’s Transit B, a.m. and p.m. January. A.M. P.M. Number of Obser- vations. Apparent Solar Time of Moon’s Transit B. Interval between the Moon’s Transit and the Time of high water. Height of Tide. Moon’s Declina- tion. Horizontal Parallax. Number of Obser- vations. Apparent Solar Time of Moon’s Transit B. Interval between the Moon’s Transit and the Time of high water. Height of Tide. Moon’s Declina. tion. Horizontal Parallax. h m h m a. in. t h m h m ft. in. 84 0 30-8 3 3-0 22 8-3 N. 19-0 57.1 83 0 29-3 3 5-0 22 10-2 S. 19-1 57-2 82 1 30-4 2 48-0 22 5-5 N. 15-3 57-4 84 1 290 2 51-3 22 7-2 S. 15-1 57-1 94 2 29-3 2 35-5 21 11-2 N. 10-0 57-1 92 2 28-8 2 40-8 21 1 1-7 S. 9-9 57-2 91 3 29-2 2 28 -2 21 5-3 N. 41 56-9 97 3 29-9 2 32-7 21 4-7 S. 4-0 56-9 97 4 29-6 2 24-2 20 5-9 S. 1-7 56-8 92 4 30-3 2 33-6 20 61 N. 21 56-9 95 5 29-2 2 35-5 19 6-3 S. 8-2 56-9 89 5 31-0 2 47-7 19 8-1 N. 8-2 56-8 91 6 28-9 3 3-9 19 5-8 S. 13-1 56-9 88 6 29-8 3 15-0 19 8-2 N. 13-5 56-9 89 7 30-1 3 38-0 20 0-9 S. 17-7 57-0 87 7 28-5 3 43-4 20 2-7 N. 17-5 57-0 83 8 30-4 3 51-2 21 0-1 S. 20-8 57-2 86 8 29-5 3 54-3 20 11-7 N. 20-7 57-1 73 9 28-1 3 50-7 21 10-8 S. 22-4 57-2 81 9 30-2 3 50-7 21 71 N. 22-5 572 83 10 28-0 3 38-0 22 4-9 S. 22-5 57-1 79 10 30-3 3 37-5 22 1-4 N. 22-9 57-4 79 11 28-3 3 19-2 22 8-0 S. 21-2 57-2 79 11 30-0 3 20-5 22 6-8 N.21-1 57-2 Sun’s Declination S. 21°. February. 86 0 29-2 3 3-5 22 9-2 N. 10-0 57-2 79 0 31-2 3 7-8 23 0-4 S. 9-8 57-3 81 1 27-5 2 48-6 o 2 10-0 N. 4-3 57-2 88 1 29-1 2 52-9 22 6-3 S. 4-0 57-2 91 2 28-0 2 36-0 22 1-5 S. 1-8 57-1 81 2 28-9 3 411 22 1-3 N. 2-2 57-2 86 3 28-9 2 27-1 21 4-6 S. 7-8 57-0 89 3 29-3 2 27-1 21 3-2 N. 8-0 56-9 84 4 30-1 2 19-8 20 11 S. 13-6 56-6 82 4 29-7 2 26-4 20 0-7 N. 13-8 56-8 77 5 30-0 2 28-2 19 1-3 S. 18-1 56-5 75 5 29-0 2 37-1 19 31 N. 18-1 56-6 73 6 29-6 3 6-9 19 1-6 S. 20-6 58-7 78 6 29-9 3 12-0 19 1-3 N. 20-6 56-7 74 7 28-5 3 41-3 20 0-2 S. 22-4 56-7 70 7 29-7 3 46-2 19 10-1 N. 22-5 56-9 73 8 29-4 3 54-4 20 11-9 S. 22-5 56-8 69 8 28-0 3 59-5 20 6-9 N. 22-8 56-9 71 9 28-5 3 50-9 21 8-6 S. 21-4 57-1 78 9 28-7 3 51-2 21 5-0 N.21-4 57-1 80 10 29-9 3 37-8 22 6-6 S. 18-5 57-3 77 10 30-1 3 36-6 22 1-5 N. 18-5 57 -2 81 11 31-6 3 22-1 22 9-8 S. 150 57-3 76 11 30-0 3 19-0 22 9-2 N. 14-7 573 Sun’s Declination S. 13°. March. 91 0 29-1 3 5-7 22 11-6 S. M 57-0 87 0 29-5 3 9-4 22 9-9 N. 17 57-3 89 1 28-7 2 50-6 22 9-0 S. 6-9 57-1 96 1 31-0 2 50-5 22 7-5 N. 7-4 57 1 94 2 28-8 2 34-8 22 1-4 S. 32-6 56-9 82 2 30-5 2 35-6 21 10-3 N. 130 56-9 84 3 29-1 2 20-9 21 1-8 S. 17-3 56-8 86 3 28-4 2 22-2 20 9-8 N. 17-3 56-8 83 4 29-1 2 15-9 20 0*5 S. 20 -2 56-7 84 4 28-4 2 17-6 19 7-3 N. 20-4 56-6 84 5 30-0 2 27-1 19 1-6 S. 21-9 56-7 82 5 30'0 2 29-9 18 7-9 N. 22-3 567 84 6 30-2 3 9-0 19 2-6 S. 22-8 56-8 79 6 28-9 3 10-2 18 10-5 N. 22-7 56-8 80 7 29-7 3 46-9 20 2-3 S. 21-8 56-9 83 7 28-1 3 47-9 19 6-0 N. 217 56-9 86 8 28-7 3 57-8 21 3-0 S. 19-2 57-2 91 8 29-3 3 58-7 20 8-8 N. 19-0 57-2 89 9 28-9 3 51-9 22 0-4 S. 15-7 57-3 86 9 30-3 3 49-0 21 9-0 N. 15-3 57-3 89 10 30-5 3 38-2 22 7-8 S. 10-6 57-6 91 10 30-2 3 35-2 22 5-4 N. 10-4 57-3 96 11 30-5 3 24-4 22 11-9 S. 4-7 57-4 91 11 30-3 3 23 0 22 10-5 N. 47 57-6 Sun’s Declination S. 2°. April. 84 0 29-0 3 8-2 23 0-8 S. 12-2 57-3 86 0 29-2 3 9-6 22 11-3 N. 12-4 57-3 83 1 29-0 2 51-7 22 6-9 S. 16-4 57-3 82 1 28-8 2 52 1 22 4-6 N. 17-0 57 -2 79 2 28-9 2 35-0 22 0-6 S. 20-0 57-0 82 2 29-0 2 34-6 21 8-5 N. 19-9 57-0 78 3 29-0 2 22-6 21 1-4 S. 21-8 56-8 76 3 29-1 2 19-8 20 90 N.21-9 56-9 79 4 30-2 2 17-9 20 1-8 S. 22-6 56-7 76 4 28-0 2 12-6 19 6-8 N. 22-6 56-7 79 5 30-8 2 34-7 19 51 S. 21-9 56-6 78 5 27 2 2 28-0 18 10-0 N.21-8 56-5 78 6 29-1 3 116 19 7-3 S. 20-0 56-7 87 6 28-4 3 79 18 10-7 N. 19-7 567 89 7 28-9 3 44-6 20 6-0 S. 15-7 56-7 85 7 29-6 3 42-1 19 9-7 N. 15-9 56-7 87 8 29-3 3 56-4 21 6-3 S. 115 57-0 88 8 29-1 3 52-6 21 0-3 N. 110 56-9 95 9 29-9 3 50-4 22 4-0 S. 5-4 57-2 91 9 30-0 3 49-3 22 0-2 N. 5-3 57-1 83 10 28-2 3 40-6 22 10-5 N. 0-6 57-4 92 10 29-9 3 38-6 27 8-4 S. 0-8 573 92 11 28-5 3 23-9 23 1-3 N. 6-3 57-4 87 11 29-3 3 22- 1 23 1-4 S. 6-9 57-4 Sun’s Declination N. 19°. MR. LUBBOCK ON THE TIDES 127 Table XX. (f.) (Continued.) May. A.M. P.M. Number of Obser- vations. Apparent Solar Time of Moon’s Transit B. Interval between the Moon’s Transit and the Time of high water. Height of Tide. Moon’s Declina- tion. Horizontal Parallax. Number of Obser- vations. Apparent Solar Time of Moon’s Transit B. Interval between the Moon’s Transit and the Time of high water. Height of Tide. Moon’s Declina- tion. Horizontal Parallax. h m h m a. in. h m h m ft. in. 81 0 29-3 3 7-5 22 11-3 S. 19-7 57-7 85 0 30-7 3 6-4 22 9-3 N. 19-9 57-5 82 1 28-7 2 51-7 22 7-4 S. 21-9 57-5 79 1 310 2 51-5 22 3-8 N.21-7 57-5 83 2 29-4 2 37-2 21 10-3 S. 22-5 57-2 82 2 30-6 2 31-8 21 5-9 N. 22-8 57-2 80 3 29-4 2 26-6 21 2-1 S. 21-8 56-9 83 3 30-9 2 18-4 20 7-6 N.21-8 56-9 86 4 29-2 2 24-8 20 4-4 S. 19-9 56-8 84 4 30-3 2 18-6 19 10-1 N. 19-7 56-9 87 5 29-4 2 43-5 20 0-2 S. 16-3 56-7 84 5 29-3 2 31-4 19 4-2 N. 16-4 56-6 90 6 29-7 3 16-3 20 1-8 S. 11-7 56-5 93 6 29-2 3 7-7 19 5-8 N. 11-4 56-5 95 7 29-0 3 42-5 20 9-8 S. 5-9 567 97 7 30-5 3 36-1 20 3-5 N. 5-7 56-7 94 8 28-7 3 52-9 21 7-0 N. 0 0 56-8 94 8 30-9 3 48-4 21 3-1 S. 0-2 56-8 94 9 30-2 3 50-8 22 3-3 N. 6-1 57-0 89 9 29-8 3 477 22 0-7 S. 6-4 57-0 91 10 30-4 3 39-2 22 8-2 N. 120 57-3 85 10 28-0 3 38-7 22 7-7 S. 11-6 57-2 85 11 30-1 3 25-5 22 9-8 N. 16-9 57-4 90 11 27-6 3 23-6 22 9-9 S. 16-6 57-3 Sun’s Declination N. 19°. June. 77 0 26-3 3 7-7 22 8-3 S. 23-0 57-3 80 0 30-1 3 3-8 22 5-3 N. 22-7 57-3 79 1 27-4 2 54-3 22 5-3 S. 21-9 57-5 77 1 31-2 2 48-0 22 2-2 N. 21-8 57-2 83 2 28-4 2 41-7 22 0-3 S. 19-2 57-3 80 2 30-7 2 34-3 21 9-0 N. 19-3 57-3 86 3 29-3 2 33-6 21 4-5 S. 16-3 56-9 86 3 30-7 2 23-9 21 1-4 N. 15-8 57-1 90 4 30-2 2 35-9 20 9-4 S. 11-6 56-9 86 4 29-7 2 25-2 20 4-8 N. 11-0 56-8 94 5 30-4 2 52-3 20 1-9 S. 5-9 56-6 92 5 28-8 2 37-5 19 11-8 N. 5-9 56-8 90 6 30-4 3 18-2 20 2-2 N. 0-7 567 94 6 29-2 3 6-1 19 9-7 S. 0-5 56-5 91 7 29-5 3 41-3 20 8-5 N. 6-3 567 88 7 29-1 3 33-7 20 5-8 S. 6-8 56-9 87 8 29-1 3 47-9 21 3-0 N. 12-1 56-9 92 8 29-7 3 47-5 21 21 S. 11-9 56-9 82 9 28-4 3 47-4 21 10-0 N. 16-5 57-0 79 9 29-7 3 47-7 21 10-0 S. 17-2 57-0 1 81 10 28-9 3 36 1 22 30 N. 20-0 571 80 10 29-7 3 36-7 22 3-9 S. 19-9 57-1 i 76 11 29-2 3 21-6 22 6-4 N. 22-1 57-4 73 11 28-3 3 23-3 22 6-7 S. 21-9 571 Sun’s Declination N. 23°. July. 82 0 30-0 3 9-9 22 7-6 S. 19-1 571 77 0 30-2 3 2-9 22 7-2 N. 19-3 57-3 80 1 28-3 2 57-8 22 7-0 S. 15-9 57-3 87 1 28-5 2 48-0 22 5-8 N. 15-4 57-0 97 2 30-3 2 44-3 22 2-4 S. 11-0 57-1 89 2 28-9 2 36-8 22 1-8 N. 11-0 57-1 90 3 30-3 2 39-5 21 61 S. 4-8 57-1 96 3 29-1 2 30-2 21 5-9 N. 4-9 57-1 98 4 28-8 2 38-6 20 8-8 N. 0-9 56-9 100 4 29-8 2 28-3 20 8-7 S. 1-4 56-9 96 5 28-3 2 52-3 20 1-4 N. 7-0 56-9 ' 95 5 30-4 2 40-8 20 0-7 S. 7-1 56-9 92 6 28-3 3 18-9 19 10-6 N. 12-6 56-8 93 6 29-7 3 9-9 19 10-3 S. 12-6 56-8 88 7 28-1 3 40-3 20 4-2 N. 16-4 56-8 87 7 30-0 3 38-4 20 3-8 S. 17 1 57-0 82 8 28-2 3 51-5 20 11-7 N. 201 56-9 83 8 29-7 3 53 1 21 1-3 S. 20-1 56-9 80 9 28-2 3 49-2 21 7-7 N. 22-3 57-1 82 9 30-1 3 52 0 21 9-3 S. 22-3 571 79 10 29-2 3 37-6 22 1-5 N.23-1 571 75 10 30- 1 3 41-4 22 4-2 S. 22-8 57-1 83 11 31-1 3 19-4 22 4-6 N.21-4 57-1 81 11 29-9 3 25-2 22 6-6 S. 21-6 57-3 Sun’s Declination N. 21° August. 92 0 301 3 13-9 22 10-0 S. 10-9 57-0 87 0 31-1 3 60 22 10-7 N. 10-4 57-0 87 1 29-1 2 57 1 22 7-3 S. 5-2 56-9 91 1 30-3 2 49-9 22 8-6 N. 4-8 56-9 91 2 28-2 2 45-3 22 0-5 N. 0-8 57-0 90 2 29-4 2 38-6 22 2-8 S. 1-2 57-0 92 3 27-9 2 36- 1 21 3-0 N. 71 56-8 92 3 30-2 2 26-2 21 5-8 S. 7-4 56-9 93 4 29-2 2 31-7 20 40 N. 12-4 56-8 89 4 29-6 2 23-3 20 6-9 S. 12-6 56-7 88 5 29-2 2 431 19 5-7 N. 17-2 56-9 86 5 28-9 2 33-8 19 7-2 S. 17-4 56-5 87 6 29-6 3 13-0 19 3-2 N. 20-2 56-9 88 6 28-7 3 10-5 19 5-6 S. 20-3 56-9 86 7 31-4 3 42-6 19 9-7 N. 22-2 57-0 82 7 29-0 3 44-7 20 2-8 S. 22-3 57-0 81 8 31-9 3 54-6 20 9-0 N. 22-3 57-1 81 8 28-3 4 11 21 1-6 S. 22 -7 571 82 9 31-5 3 50-2 21 6-6 N.21-7 57-3 83 9 28-3 3 57-2 21 10-2 S. 21-7 57-2 80 10 31-4 3 35-2 22 1-7 N. 19-4 57-3 85 10 28-8 3 45-7 22 5-4 S. 19-3 57-3 87 11 30-5 3 24 0 22 7-3 N. 15-8 57-2 84 11 291 3 32-5 22 9-8 S. 15-7 57-3 Sun’s Declination N. 14°. 128 MR. LUBBOCK ON THE TIDES Table XX. (/.) (Continued.) September. A.M. P.M. Number of Obser- vations. Apparent Solar Time of Moon’s Transit B. Interval between the Moon’s Transit and the Time of high water. Height of Tide. Moon’s Declina- tion. Horizontal Parallax. Number of Obser- vations. Apparent Solar Time of Moon’s Transit B. Interval between the Moon’s Transit and the Time of high water. Height of Tide. Moon’s Declina- tion. Horizontal Parallax. h m h m ft. in. / h ra h m ft. in. / 83 0 30-0 3 15-7 22 11-0 S. 0-3 57-4 96 0 28-8 3 6-7 23 0-8 N. 0-1 57-4 93 1 29-0 2 58-7 22 6-3 N. 6-6 571 89 1 30-5 2 49-1 22 8-5 S. 6-6 57-1 86 2 29-4 2 40-7 21 111 N. 11-9 571 87 2 30-2 2 36-0 22 2-7 S. 12-3 56-9 83 3 29-0 2 31 0 20 1 1-2 N. 16-5 56-9 80 3 29 1 2 23-5 21 2-7 S. 16-8 56-9 82 4 30-0 2 19-8 19 9-2 N. 201 56-7 82 4 28-7 2 15-2 20 1-6 S. 20-1 56-7 81 5 31-7 2 30-2 18 10-7 N. 22-1 56-6 76 5 28-3 2 27-0 19 4-8 S. 22-0 56-7 76 6 30-9 3 10-0 18 7-8 N. 22-8 56-7 79 6 27-8 3 14-4 19 31 S. 23-0 56-7 78 7 29-5 3 43-1 19 6-4 N.22-1 56-9 82 7 28-7 3 521 20 2-9 S. 22-0 56-7 82 8 28-4 3 55-8 20 7-2 N. 19-7 57-1 82 8 28-4 4 3-6 21 3-8 S. 19-9 56-9 88 9 29-9 3 50-5 21 8-6 N. 16-4 57-2 86 9 29-1 3 58-6 22 0-5 S. 16-1 57-2 89 10 30-6 3 410 22 5-7 N. 110 57-3 87 10 29-5 3 47 5 22 7-6 S. 11-9 57-3 82 11 29-3 3 23-7 22 10-7 N. 61 57-3 95 11 30-2 3 311 22 11-4 S. 5-4 57-5 Sun’s Declination N. 3°. October. 86 0 29-8 3 14-1 22 10-1 N. 11-5 57-5 89 0 30-2 3 7-5 23 01 S. 11-5 57-5 89 1 29-9 2 55-0 22 6-4 N. 15-6 57-4 84 1 29-5 2 51-0 22 6-4 S. 16-3 57-4 84 2 30-9 2 36-2 21 7-5 N. 19-8 56-9 82 2 28-5 2 33-6 22 1-2 S. 19-2 57-1 80 3 30-0 2 21-8 20 7-5 N. 22 0 56-9 84 3 27-8 2 20-9 21 1-3 S. 21-8 56-9 77 4 29-3 2 11-2 19 7-6 N. 22-7 56-8 80 4 28-4 2 13-8 20 1-8 S. 22-7 56-8 81 5 29-0 2 20-4 18 90 N. 22-2 56-7 83 5 29-3 2 29 1 19 4-4 S. 22-0 56-6 87 6 30-9 2 58-0 18 9-3 N. 19-6 56-7 83 6 30-4 3 13-3 19 4-8 S. 20-0 56-6 83 7 31-6 3 37-8 19 8-1 N. 16-9 56-6 84 7 29-7 3 51-3 20 6-3 S. 16-6 56-6 92 8 30-3 3 51-4 20 10-6 N. 12-6 56-8 88 8 29-1 4 1-9 21 6-7 S. 12-4 56-9 90 9 28-8 3 47-8 21 11-3 N. 7-0 570 97 9 28-5 3 56-5 22 2-5 S. 7-0 571 98 10 28-8 3 30-6 22 8-2 N. 0-9 57-4 92 10 29-2 3 46-5 22 9-9 S. 0-3 57-4 95 11 29-7 3 23-4 22 111 S. 5-6 57-6 94 11 30-3 3 30-6 22 11-6 N. 5-7 57-3 Sun’s Declination S. 9°. November. 81 0 30-5 3 8-5 22 5-2 N. 19-8 57-5 81 0 27-2 3 6-2 22 8-4 S. 19-2 57-4 80 1 31-5 2 48-7 22 1-7 N.21-9 57-4 78 1 26-3 2 49-7 22 4-7 S. 21-7 57-4 75 2 31-8 2 32-6 21 7-3 N. 22-6 57-3 77 2 26-7 2 33-7 21 11-5 S. 22-5 57-3 81 3 30-9 2 21-4 20 9-1 N.21-8 57-2 82 3 27-7 2 25-4 21 4-0 S. 22-1 57-2 79 4 30-5 2 14-4 19 8-1 N. 20-4 56-9 82 4 28-4 1 23-1 20 4-9 S. 19-8 56-8 85 5 29-5 2 24-7 19 1-0 N. 170 56-6 84 5 27-9 2 39-8 20 0-2 S. 17-0 56-6 91 6 30-2 3 0-4 19 1-6 N. 121 56-7 94 6 29-8 3 13-3 19 10-3 S. 121 56-7 87 7 29-7 3 30-6 20 0-7 N. 6-4 56-8 90 7 30-6 3 44 1 20 8-5 S. 6-2 56-8 94 8 29-7 3 45-8 21 0-7 N. 0-5 56-8 88 8 30-1 3 55-9 21 6-8 S. 01 56-8 85 9 29-6 3 43-7 22 0-1 S. 5-6 57-1 89 9 29-3 3 49-7 22 1-6 N. 5-8 571 89 10 29-0 3 35-6 22 4-4 S. 11-2 57-2 87 10 30-2 3 40-3 22 5-6 N. 11-6 57-2 78 | 11 28-3 3 20-6 22 9-7 S. 16-2 57-4 81 11 30-2 3 26-6 22 9-3 N. 16-1 57-3 Sun’s Declination S. 18°. December. 81 0 28-6 3 4-9 22 4-7 N. 22-4 57-4 76 0 30-2 3 4-4 22 7-9 S. 22-4 57-2 78 1 29-6 2 47-3 22 1-9 N. 22-2 57-3 81 1 296 2 48-0 22 3-7 S. 21-8 57-3 82 2 29-2 2 32-2 21 9-3 N. 19-6 57-3 83 2 30-7 2 34-6 22 0-8 S. 19-6 57 1 89 3 29-5 2 24-3 21 01 N. 160 57-1 86 3 31-4 2 31-6 21 3-4 S. 16-0 571 91 4 29-2 2 22-7 20 4-5 N. 11-5 57-0 94 4 30-2 2 30-6 20 6-8 S. 10-9 56-9 101 5 29-9 2 30-9 19 6-7 N. 5-5 56-8 96 5 29-6 2 47 3 20 2-7 S. 5-3 56-9 89 6 29-7 3 20 19 7-7 S. 0-2 56-7 92 6 28-7 3 14-3 20 0-7 N. 0-7 56-7 97 7 28-4 3 28-4 20 3-7 S. 6-6 56-7 96 7 28-3 3 40-4 20 6-8 N. 6-7 567 89 8 28-5 3 43 0 21 2-6 S. 12-1 570 95 8 29-8 3 49-6 21 41 N. 12-3 56-9 87 9 28-7 3 45-5 21 9-7 S. 16-4 571 80 9 29-9 3 49-9 21 11-8 N. 16-9 571 82 10 29-9 3 35-4 22 4-5 S. 19-7 571 78 10 27-3 3 38-4 22 2-5 N. 19-7 57-2 81 11 30-0 3 21-2 22 5-3 S. 22-3 57-3 82 11 27-0 3 21-7 22 4-9 N. 221 57-1 Sun’s Declination S. 23°. In the above Table the Lower Transits have been incorporated with the upper, the declinations are those corresponding to the Upper Transits. MR. LUBBOCK ON THE TIDES 129 Table XXL (g.) Showing1 the Diurnal Inequality at London, or the Difference in the Interval be- tween the Apparent Solar Time of the Moon’s Transit and the Time of High Water, and the Interval in Table XVI., and the Difference between the Height of High Water and the Height in Table XVII. Diurnal Inequality. Apparent Solar Time of Moon’s Transit B. January. February. March. Interval. Height. Moon’s Declination. Interval. Height. Moon’s Declination. Interval. Height. Moon’s Declination. h m m feet. m feet. m feet. P.M. 0 30 + 0'9 + •07 S. 19-1 + 2-6 + •14 S. 9-8 + 1-6 — •09 N. 1-7 1 30 + 1-7 + •12 S. 15-1 + 2-2 — •15 S. 4-0 + 0-2 — •05 N. 7-4 2 30 + 2-5 •00 S. 9-9 + 2-7 •00 N. 2-2 + 0-7 — •12 N. 130 3 30 + 2-2 •00 S. 4-0 0-0 — •05 N. 8-0 + 0-5 — •20 N. 17-3 4 30 + 4-6 + ■02 N. 2-1 + 3-1 — •04 N. 13-8 + 1-5 — •19 N. 20-4 5 30 + 5-9 + •12 N. 8-2 + 4-9 + •07 N. 18-1 + 1-5 — •24 N. 22-3 6 30 + 5-3 + •09 N. 13-5 + 21 — •02 N. 20-6 + 1-0 — •15 N. 22-7 7 30 + 30 + •08 N. 17-5 + 2-3 — •12 N. 22-5 + 0-7 — •31 N.21-7 8 30 + 1-3 + •02 N. 20-7 + 2-5 — •19 N. 22-8 + 0-4 _ •26 N. 19-0 9 30 + 0-1 •17 N. 22-5 + 0-2 — •14 N.21-4 13 _ •16 N. 15-3 10 30 + 0-1 — •20 N. 22-9 0-6 — •22 N. 18-5 — 1-7 — ■08 N. 10-4 11 30 + 0-8 - •05 N.21-1 - 1-8 - •02 N. 14-7 - 0*5 - •07 N. 4-7 A.M. 0 30 0-7 •07 N. 19-0 21 •11 N. 10-0 20 + •11 S. 11 1 30 — 1-6 — •06 N. 15-3 — 2-5 + •14 N. 4-3 — 0-2 + •05 S. 6-9 2 30 — 2-5 — •01 N. 10-0 — 2-4 + ■01 S. 1-8 — 0-4 + •10 S. 12-6 3 30 — 2-3 + •03 N. 41 — 0-4 + •03 S. 7-8 — 0-7 + •18 S. 17-3 4 30 — 4-2 + •01 S. 1-7 — 2-6 + •04 S. 13-6 — 0-8 + •23 S. 20-2 5 30 — 5-8 •09 S. 8-2 — 41 •04 S. 181 — 1-3 + •23 S. 21-9 6 30 — 5-3 — •10 S. 13-1 _ 2-7 •00 S. 20-6 — 0-8 + •19 S. 22-8 7 30 — 2-7 — •10 S. 17-7 — 2*5 + •13 S. 22-4 — 0-6 + •35 S. 21-8 8 30 — 1-6 - •01 S. 20-8 — 2-7 + •21 S. 22-5 — 0-5 + •27 S. 19-2 9 30 0-2 + •18 S. 22-4 — 0-2 + •16 S. 21-4 + 1-3 + •15 S. 15-7 10 30 — 0-1 + •18 S. 22-5 + 0-6 + •19 S. 18-5 + 1-7 + ■05 S. 10-6 11 30 — 10 + •06 S. 21-2 + 1-7 + •02 S. 15-0 + 0-8 + •05 S. 4-7 April. May. June. P.M. 0 30 + 0-7 •06 N. 12-4 0-3 •08 N. 19-9 1-5 •12 N. 22-7 1 30 + 0-3 — ■11 N. 17-0 + 01 — •14 N.21-7 — 2-5 — •07 N.21-8 2 30 0-1 _ •16 N. 19-9 2-6 _ •16 N. 22-8 — 3-6 — •11 N. 19-3 3 30 — 1-5 _ •20 N.21-9 — 41 _ •22 N.21-8 _ 5-2 — •13 N. 15-8 4 30 — 2-6 — •32 N. 22-6 — 3-9 — •25 N. 19-7 — 5-4 — •20 N. 11-0 5 30 — 2-5 — •32 N.21-8 — 61 — •34 N. 16-4 — 7-6 — •13 N. 5-9 6 30 — 1-5 — •35 N. 19-7 — 4-2 _ •33 N. 11-4 — 5-5 — ■08 S. 0-5 7 30 — 1-4 — •36 N. 15-9 — 3-4 _ •29 N. 5-7 — 3-7 _ •13 S. 6-8 8 30 — 2-0 _ •23 N. 11-0 — 2-2 _ •18 S. 0-2 — 0-2 _ •04 S. 11-9 9 30 — 0-7 — •13 N. 5-3 — 1-6 — •11 S. 6-4 + 0-2 — •01 S. 17-2 10 30 — 0-7 — •09 S. 0-8 — 0-6 — •01 S. 11-6 + 0-4 + •03 S. 19-9 11 30 - 0-8 •00 S. 6-9 - M + •01 S. 16-6 + 0-8 + •02 S. 21-9 A.M. 0 30 ~ 0-8 + •07 S. 12-2 + 0-3 + •06 S. 19-7 + 1-4 + •11 S. 23-0 1 30 — 0-2 + •06 S. 16-4 0-2 + •13 S. 21-9 + 2-8 + •07 S. 21-9 2 30 + 0-3 + •18 S. 20-0 + 2-6 + •18 S. 22-5 + 3-4 + •13 S. 19-2 3 30 + 1-6 + •18 S. 21-8 + 4-1 + •29 S. 21-8 + 4-5 + •14 S. 16-3 4 30 + 2-3 + •30 S. 22-6 + 3-1 + •25 S. 19-9 + 4-8 -F •15 S. 11-6 5 30 + 2-0 + •28 S. 21-9 + 5-6 + •31 S. 16-3 + 7-3 + •12 S. 5-9 6 30 + 1-9 + •37 S. 20 0 + 4-1 + •33 S. 11-7 + 5-7 + •16 N. 0-7 7 30 + 1-2 + •34 S. 15-7 + 3-3 + •27 S. 5-9 + 3-7 + •14 N. 6-3 8 30 + 1-9 + •25 S. 11-5 + 2-3 -F ■19 0-0 + 0-2 + •05 N. 121 9 30 + 0-6 + •16 S. 5-4 + 1-5 + •10 N. 6-1 — 0-3 + •01 N. 16-5 10 30 + 10 + •08 N. 0-6 + 0-5 •03 N. 120 — 0-4 ■03 N. 20'0 11 30 + 0-8 •00 N. 6-3 + 1-4 — •02 N. 16-9 — 0-7 •02 N. 22- 1 MDCCCXXXVII, s 130 MR. LUBBOCK ON THE TIDES Table XXI. ( g .) (Continued.) Diurnal Inequality. Apparent Solar Time of Moon’s Transit B. July. August. September. Interval. Height. Moon’s Declination. Interval. Height. Moon’s Declination. Interval. Height. Moon’s Declination. h m m feet. m feet. m feet. o P.M. 0 30 _ 3-8 — •04 N. 19-3 — 3-9 + •03 N. 10-4 — 4-3 + •08 N. 0-1 1 30 — 4-6 •02 N. 15-4 — 3-3 + •06 N. 4-8 — 4-7 + •10 S. 6-6 2 30 4-0 _ •03 N. 11-0 _ 3-3 + •11 S. 1-2 — 2-1 + •17 S. 12-3 3 30 _ 4-5 •02 N. 4-9 — 5-0 + •15 S. 7-4 — 3-8 + •15 S. 16-8 4 30 5-2 + •01 S. 1-4 — 4-2 + •12 S. 12-6 — 21 + •16 S. 20-1 5 30 _ 6-4 •01 S. 7-1 — 3-8 + •13 S. 17-4 — 0-9 + •24 S. 22-0 6 30 _ 4-9 _ •02 S. 12-6 — 1-0 + •10 S. 20-3 + 3-3 + •31 S. 23-0 7 30 0-9 _ •05 S. 17-1 + 11 +- •23 S. 22-3 + 4-4 + •38 S. 22-0 8 30 + 0-8 + •06 S. 20-1 + 3-3 + •24 S. 22-7 + 3-8 + •38 S. 19-9 9 30 + 1-5 + •04 S. 22-3 + 3-2 + •18 S. 21-7 + 4-0 + •18 S. 161 10 30 + 2-0 + •11 S. 22-8 + 4-8 + •17 S. 19-3 + 3-3 + •07 S. 11-9 11 30 + 2-8 + •06 S. 21-6 + 4-2 + •11 S. 15-7 + 3*5 + •01 S. 5-4 A.M. 0 30 + 3-3 + •03 S. 19-1 + 3-7 •03 S. 10-9 + 5-0 •07 S. 03 1 30 + 4-9 + •01 S. 15-9 + 3-6 — •06 S. 5-2 + 4-6 — •11 N. 6-6 2 30 + 3-8 + *05 s. n o + 3-2 — •11 N. 0-8 + 21 — •18 N. 119 3 30 + 4-8 + •03 S. 4-8 + 51 — •12 N. 71 + 3-7 — •14 N. 16-5 4 30 + 5-3 •00 N. 0-9 + 3-9 — •15 N. 12-4 + 2-2 — •17 N. 201 5 30 + 6-2 + •03 N. 7-0 + 3-6 — •12 N. 17-2 + 0-9 — •20 N. 22-1 0 30 + 4-9 + •02 N. 12-6 + 14 — •11 N. 20-2 2-2 — •32 N. 22-8 7 30 + 1-3 + •06 N. 16-4 1-5 _ •25 N. 22-2 — 4-7 — •40 N. 22-1 8 30 0-9 •05 N. 20-1 — 3-0 _ •23 N. 22-3 — 3-8 _ •38 N. 197 9 30 1-6 — •05 N. 22-3 _ 31 — •20 N.21-7 — 3-9 — •16 N. 16-4 10 30 2-0 — •11 N. 231 — 5-1 — •18 N. 19-4 — 3-0 _ •09 N. 11-0 11 30 - 2-7 — ■08 N. 21-4 — 4-0 - •08 N. 15-8 — 4-1 — •01 N. 61 October. November. December. P.M. 0 30 3-1 + •09 S. 11-5 1-5 4- •12 S. 19-2 + 0-2 + •16 S. 22-4 1 30 — 2-0 •00 S. 16-3 — 01 + •08 s. 217 + 0-4 4- •09 S. 21-3 2 30 — 17 4" •19 S. 19-2 — 0-9 4- •13 s. 22-5 4- 1-5 + •19 S. 19-6 3 30 — 0-5 + ■21 s. 21-8 + 1-9 4- •24 s. 22- 1 4- 37 + •16 S. 16-0 4 30 + 1-4 + •24 s. 227 4- 4-5 + •34 s. 19-8 + 3-8 + •11 S. 10-9 5 30 + 4-2 + ■30 s. 220 4- 8-0 4- •46 s. 170 + 8-5 4- •34 S. 5-3 6 30 + 7-8 + •33 s. 20-0 + 6-4 + •36 s. 121 + 6-3 + •21 N. 07 7 30 + 6-9 + •44 s. 16-6 + 6-6 + •30 s. 6-2 + 61 + •12 N. 67 8 30 + 5-4 + •36 s. 12-4 + 5-3 4- •27 s. 0-1 4- 3-2 4- •06 N. 12-3 9 30 + 41 + •13 s. 7-0 + 2-9 4- •06 N. 5-8 + 2-4 + •07 N. 16-9 10 30 + 51 + •08 s. 0-3 + 2-5 + •05 N. 11-6 4- 1-2 •06 N. 197 11 30 + 3-9 + ■07 N. 57 + 3-3 •02 N. 16-1 0-2 4- •01 N. 224 A.M. 0 30 + 3-5 •08 N. 11-5 4- 1-5 •16 N. 19-8 + 0-1 •16 N. 22-4 1 30 + 21 •00 N. 15-6 + 0-2 — •09 N. 21-9 0-3' _ •07 N. 22-2 2 30 + 1-6 — •20 N. 19-8 0-2 -v- ■11 N. 22 -6 _ 1-5 •20 N. 194 3 30 + 0-5 — •21 N. 220 _ 2-0 — •25 N. 21-8 _ 3-6 •13 N. 16'0 4 30 1-4 — •26 N. 227 _ 5-1 — •39 N. 20-4 4-3 •14 N. 11-5 5 30 — 37 — •35 N. 22-2 _ 7-9 — •46 N. 17-0 _ 7-6 _ •29 N. 5-5 6 30 — 8-0 — •3 4 N. 19-6 _ 67 — •37 N. 121 _ 6-4 •22 S. 0-2 7 30 — 7-0 — •45 N. 16-9 — 67 — •33 N. 6-4 _ 5-9 •14 S. 6-6 8 30 — 5-3 — •33 N. 12-6 — 4-8 _ •23 N. 0-5 _ 3-4 •06 S. 124 9 30 — 4-6 — •13 N 7-0 _ 31 _ •06 S. 5-6 2-2 •07 S. 16-4 10 30 — 4-9 — •05 N 0-9 _ 2-4 — •04 s. 11-2 _ 1-3 + •08 S. 197 11 30 3-4 — •03 S. 5-6 — 3-3 + •01 s. 16-2 + 01 •01 S. 22-3 | MR. LUBBOCK ON THE TIDES. 131 Table XXII. ( h .) Showing a Comparison between the Semimenstrual Inequality at London in the Interval and in the Height, as deduced from theory and from the results of observation contained in Tables XVI. and XVII. Moon’s Hor. Par. 57f, and Decl. 15°. Apparent Solar Time of Moon’s Transit B. Interval. + a constant. Height. h. Theory. Observation. Theory. Observation . h m h m h m feet. feet. 0 0 3 15-3 22-76 0 30 3 71 3 7-1 22-77 22-72 1 0 2 58-8 22-70 1 30 2 51-3 2 50'9 22-58 22-44 2 0 2 431 22-35 2 30 2 36-8 2 36-5 22-09 21-92 3 0 2 30-8 21-73 3 30 2 26-8 2 26-7 21-35 21-14 4 0 2 24-8 20-90 4 30 2 23-3 2 24-0 20-47 20-23 5 0 2 29-8 20-10 5 30 2 37-8 2 37’5 19-75 19-57 6 0 2 52-8 19-58 6 30 3 10-8 3 10-8 19-47 19-55 7 0 3 25-8 19-64 7 30 3 42-8 3 41-5 19-85 20-26 8 0 3 48-8 20-25 8 30 3 53-8 3 53-4 20-63 21-15 9 0 3 51-8 21-10 9 30 3 49-8 3 50-4 21-50 21-89 10 0 3 44-8 21-89 10 30 3 38-8 3 39-0 22-22 22-42 11 0 3 30-8 22-47 11 30 3 23-8 3 23-6 22-66 22-70 The above Inequalities from theory are the same as for the preceding London Dis- cussion*, excepting that the constant applied to ^ is now 3h 8m*4, formerly it was 3h 6m*6. They have been calculated from the expressions (See p. 11 7-) tan 2 (A) sin 2

) + cos 2 log ( A ) = 9*56284 log ( E ) = 0*63749 D = 16*79 The columns headed “ Observation” have been deduced from the quantities headed “ Mean” in Tables II. and III., by applying to them proper corrections for the devia- tions from declination 15°. * Philosophical Transactions, 1836. 1.32 MR. LUBBOCK ON THE TIDES Table XXIII. (i.) Showing the Calendar-month Inequality in the Interval and in the Height of High Water, as deduced from Bernoulli’s theory and from the results of observation contained in Tables XVI. and XVII. See Plate I. Apparent Solar Time of Moon’s Transit B. January. February. March. Apparent Solar Time of Moon’s Transit. B. d -J/ d h Moon’s Decli- nation. d ^ d h Moon’s Decli- nation. d + d h Moon’s Decli- nation. Theory. Obser- vation. Theory. Obser- vation. Theory. s Obser- vation. Theory. Obser- vation. Theory. Obser- vation. Theory. Obser- vation. li m m m feet. feet. m m. feet. feet. m m feet. feet. h m 0 30 0-0 -3-3 -•49 +•02 19 00 -1-8 +•08 +•12 10 0-0 +0-4 +•32 + •14 5 0 30 1 30 +0-3 -1-6 -•36 +•01 16 +0-1 -0-6 +•16 + •18 6 -0-4 -0-5 +•25 +•22 8 1 30 2 30 + 1-2 + 1-2 -•13 -■01 11 + 0-2 + 1-3 +■16 +•13 5 -17 -1-3 +■10 + ■09 13 2 30 3 30 +2-8 +4-2 +•03 +•28 6 00 +0-8 + •10 + •19 8 -4-1 -4-4 -11 -•14 17 3 30 4 30 -j-3-5 +5-3 +•10 + •30 5 -2-2 +0-2 -•09 -17 14 -7-2 -5-8 -•36 -•36 22 4 30 5 30 +2-5 +4-6 +•08 +•07 9 -3-6 -3-1 -•28 -•27 18 -7-8 -7-8 -•52 -•58 23 5 30 6 30 0-0 -0-8 + •01 +•06 13 0-0 -0-5 -•45 — •35 21 0-0 -0-8 -•58 -•48 23 6 30 7 30 +0-9 -0-8 -•24 -•09 18 +7-0 +2-4 -•54 -•27 23 +7-8 +6-0 -•49 -•39 22 7 30 8 30 +3-0 -0-3 -•45 -•20 21 +6-9 +3-4 -•50 -•32 22 +6-5 +5-2 -•26 -•18 19 8 30 9 30 +3-3 +0-5 -•57 -17 23 +5-2 +0-5 -•45 -•32 22 +37 +0-4 -■06 -•05 16 9 30 10 30 +21 -1-2 -•62 -•18 23 +2-4 -1-6 -•29 -•12 19 + 17 -1-9 +•16 +•05 11 10 30 11 30 +0-1 -3-9 -■60 -11 21 +07 -2-8 -•07 +•04 14 +0-3 +0-2 +■29 +•14 6 11 30 Sun’ s Decl. 21°, and Par. 8"-94. Sun’ s Decl. 13°, and Par. 8"'90. Sun’s Decl. 3°, and Par. 8"-84. April. May. June. 0 30 0-0 + 1-4 + •22 +•22 13 0-0 -0-5 -•17 +•03 20 o-o -2-0 -•34 -•22 23 0 30 1 30 -0-5 +0-5 +■04 -•01 17 -0-2 +0-2 -•28 -•07 22 +07 -0-3 -•29 -•21 22 1 30 2 30 -2-0 -20 -12 -•07 20 -07 -2-4 -•30 -•29 23 +2-2 +0-9 -•14 -•12 20 2 30 3 30 -41 -5-0 -•24 -•18 22 -0-6 -3-8 -•22 -•24 22 +5-1 +2-0 +•11 +•10 16 3 30 4 30 -6-4 -71 -•31 -•30 23 +0-2 -1-2 -•07 -•07 20 +7-8 + 7-5 +•36 +•43 11 4 30 5 30 -5-3 -3-5 -■32 -■30 22 +1-8 +2-0 +•10 +•23 17 +8‘5 +9-0 +•55 +•59 7 5 30 6 30 0-0 -0-1 -•22 -•24 20 0-0 +2-3 +•34 +•39 12 0-0 +2-0 +•67 + •54 5 6 30 7 30 + 1-9 + 1-9 -•02 -01 16 -5-4 -2-3 +•42 +•38 7 -8-2 -4-0 +•55 +•39 8 7 30 8 30 -01 +M +•20 +•14 11 -6-4 -31 +•41 + •31 5 -8-2 -5-8 +•34 + •09 12 8 30 9 30 -1-2 -0-3 +•34 +•24 6 -47 -1-1 +•34 +•28 7 -47 -3-0 +•06 -•04 17 9 30 10 30 -0-6 +0-5 +•38 + •31 5 -2-4 00 +•20 + •22 12 -2-2 -27 -•14 -•15 20 10 30 11 30 -0-3 -0-9 +■37 +■35 7 -07 +0-5 -02 +•07 17 -0-6 -1-5 -•29 -•15 22 11 30 Sun’s Decl. 10°, and Par. 8"76. Sun’ Decl. 19°, and Par. 8"70. Sun’ s Decl. 23°, and Par. 8/,-66. July. August. September. 0 30 0-0 -0-6 -•14 -•14 20 0-0 +31 +•30 +•14 11 0-0 +3-4 +•46 +•19 5 0 30 1 30 + 1-3 + 1-3 +■05 +•04 16 +0-9 +2-5 +•41 +•24 7 0-0 +2-9 +•39 +•16 8 1 30 2 30 +2-8 +4-1 +•26 +•24 11 +2-2 +5-3 +•44 +•19 4 -0-9 + 1-8 +•26 +■15 12 2 30 3 30 +6-8 +7-6 +•41 +•32 6 +2-9 +4-9 +•35 +•23 8 -27 + 1-0 +■02 -•06 17 3 30 4 30 +8-7 +9-9 +•48 +•51 5 +2-2 +4-9 +•22 +•29 13 -5-4 -5-1 -•18 -•21 20 4 30 5 30 +7'1 +9-9 +•50 +•53 8 -0-3 +2-8 •00 +•04 18 -6-4 -7-4 -•36 -•34 22 5 30 6 30 0-0 +4-4 +•42 +■37 13 00 + 1-5 -•16 -15 21 0-0 + 1-4 -•45 -•52 23 6 30 7 30 -3-7 — 2*2 +•20 +•11 17 +3-0 +2-3 -•21 -•24 22 +6-4 +6-3 -•36 -•30 22 7 30 8 30 —2-2 -1-2 -•01 -•07 20 +37 +4-4 -•24 -•24 23 +47 +6-2 -•18 -•15 20 8 30 9 30 -0-7 +0-2 — •22 -•18 23 +2-3 +3-6 -•19 -•23 22 +2-3 +4-3 +•02 -•05 17 9 30 10 30 -0-5 +0-5 -•27 -•20 23 +0-4 + 1-8 -•03 -•18 19 +0-9 +5-3 +•26 +•08 12 10 30 11 30 -0-5 -1-2 -•25 -•26 22 -0-2 +4-5 +•10 -•04 16 -01 +4-0 + •41 +•15 7 11 30 Sun’ Decl. 21°, and Par. £ "•66. Sun’ Decl. 14°, and Par. 8-"70. Sun’s Decl. 4°, and Par. 8"76. October. November. December. 0 30 0-0 + 3-2 +•13 +•10 12 o-o -0-3 -•42 -•23 20 0'0 -2-9 -77 -•26 23 0 30 1 30 -0-9 + 1-6 -■05 + •01 16 -1-0 -2-4 -•53 -•27 22 -0-5 -37 -70 -•29 22 1 30 2 30 -2-8 - 1-6 -•24 -•06 20 -2-3 -4-0 -•56 -•23 23 -0-2 -3-5 -•53 -•04 20 2 30 3 30 -5-3 - 5-0 -•37 -■27 22 -3-2 -4-0 -•47 -•16 22 + 1-3 +0-8 -■27 -02 16 3 30 4 30 -8-2 -10-4 — •45 -•29 23 -3-4 -4-8 -•34 -•13 20 +2-6 +3-2 -•01 +•26 11 4 30 5 30 -6-7 - 10-6 -•46 -•39 22 -1-2 -2-9 -•22 +•09 18 +4-1 + 1-9 +•15 +■34 7 5 30 0 30 0-0 - 4-8 -•37 -•38 20 0-0 -3-3 +•05 +•02 12 0-0 -17 +•25 +•38 5 6 30 7 30 +3-3 + 2-6 -•21 -•08 17 -2-4 -4-2 +•14 +•18 7 -3-8 -7-1 +•13 +•29 8 7 30 8 30 + 17 + 3-0 +•04 + •09 12 -2-8 -31 +•15 +•19 5 -3-0 -77 -•04 +■16 12 8 30 9 30 0-0 + 1-8 + •19 + •20 7 -21 -3-6 +•09 +•17 7 +0-9 -2-8 -•32 ■00 17 9 30 10 30 +0-2 + 2-5 + •26 +•25 5 -0-8 -10 •00 -•04 12 +0-2 — 2-2 -•53 -•15 20 10 30 11 30 +0-1 + 3-2 + •24 +•15 7 -0-2 -0-2 -•23 +•04 16 +0-6 -2-5 -70 -•30 23 11 30 Sun’s Decl. 9°, and Par. 8 '•84. Sun’s Decl. 18°, and Par. 8"-90. Sun’s Decl. 23°, and Par. 8"-94. MR. LUBBOCK ON THE TIDES 133 Table XXIV. (j.) Showing the Moon’s Parallax Inequality in the Interval and in the Height of High Water, as deduced from Bernoulli’s theory and from the results of observation contained in Table XIX. See Plate II. H. P .54'. H. P .55'. Apparent Apparent Solar Time Solar Time of Moon’s d 4 d/« d 4 d k of Moon’s Transit Transit B. Theory. Obser. vation . Theory. Obser- vation. Theory. Obser- vation. Theory. Obser- vation. B. h m m m feet. feet. m m feet. feet. h m 0 30 0-0 - 0-1 - -66 - -46 0-0 4 0-2 - -45 - -42 0 30 1 30 - 20 - 3-4 - -66 - -57 - 1-3 - 2-9 - -45 - -34 1 30 2 30 - 4-2 - 6-2 - -64 - -59 - 2-7 - 4-5 - -44 - -38 2 30 3 30 - 6-5 -12-9 - -62 - -79 - 4-2 - 8-3 - -42 - -61 3 30 4 30 - 8-7 -130 - -61 - 78 - 5-6 - 8-9 - -42 - -56 4 30 5 30 - 8-4 -11-7 - -64 - -97 - 5-2 - 8-9 - -44 - -72 5 30 6 30 0-0 - 1-8 - -66 - -79 0-0 - 2-6 - -45 - -57 6 30 7 30 + 8-4 4 0-5 - -64 - -89 4- 5-2 4 0-4 - -44 - -50 7 30 8 30 4 8-7 -j- 5-0 - -61 - -67 -j- 5-6 4 3-5 - -42 - -41 8 30 9 30 -j- 6-5 + 3-2 - -62 - -52 + 4-2 4 2-4 - -42 - -40 9 30 10 30 4 4-2 4 21 - -64 - -37 4 2-7 4 2-9 - -44 - -29 10 30 11 30 4 2-0 + 3-1 - -66 - -55 + 1-3 4 2-9 - -45 _ -42 11 30 H. P. 56'. H. P . 57'. 0 30 0-0 - 0-5 - -23 - -10 00 0-0 •00 ■00 0 30 1 30 - 0-6 - 2-2 - -23 - -19 0-0 00 •00 •00 1 30 2 30 - 1-3 - 1-7 - -23 - -23 0-0 0-0 •00 •00 2 30 3 30 - 2-0 - 2-5 - -21 - -37 0-0 00 •00 •00 3 30 4 30 - 2-7 - 4-3 - -21 - -27 00 0-0 •00 •00 4 30 5 30 - 2-5 - 6-0 - -22 - -32 0-0 00 •00 •00 5 30 6 30 0-0 — 1-0 - -23 - -25 0-0 00 •00 •00 6 30 7 30 + 2-5 - 0-6 - -22 - -20 00 0-0 •00 ■00 7 30 8 30 + 2-7 + 0-5 - -21 - -24 0-0 0-0 •00 •00 8 30 9 30 + 2-0 + M - -21 - -20 o-o 0-0 •00 •00 9 30 10 30 + 1-3 4 0-5 - -23 - -03 0-0 0-0 •00 •00 10 30 11 30 4 0-6 4 3-3 - -23 - -25 o-o 00 •00 •00 11 30 H. P. 58'. H. P. 59'. 0 30 0-0 + 2-1 + -24 4 "12 0-0 4 2-7 4 -49 4 -35 0 30 1 30 + 0-6 - 0-3 + -24 4 -23 + 1-2 4 0-8 4 -48 4 -39 1 30 2 30 + 1'3 + 2-9 + -23 4- -19 4 2-5 4 3-5 4 -47 4 -47 2 30 3 30 + 2-0 + 4-8 4 -22 4 -16 + 3-8 + 7-1 4 -45 4 -39 3 30 4 30 + 2-5 + 4-5 + -22 4- -16 4- 4-8 4 9-4 4 -45 4 -58 4 30 5 30 + 2-0 + 3-8 4 -23 4- -26 + 4-2 4 6-2 4 -46 4 -63 5 30 6 30 00 + 3-4 -f -24 4- -26 0-0 4 5-3 4 -49 4 -61 6 30 7 30 - 2-0 - 1-5 4- -23 4 -31 - 4-2 - 3-0 4 -46 4 -53 7 30 8 30 - 2-5 + 0-1 4- -22 + -19 - 4-8 - 31 4 -45 4 -46 8 30 9 30 - 2-0 - 1-9 4 -22 + -33 - 3-8 - 2-9 4 -45 4 -34 9 30 10 30 - 1-3 - 1-2 4- -23 4- -29 - 2-5 1-8 4 -47 4 -53 10 30 11 30 - 0-6 + 1-8 + -24 + 'll - 1-2 4 2-4 4 -48 4 -31 11 30 H. P. 60'. H. P. 61'. 0 30 0-0 + 1-0 4- '75 4- -67 0-0 4 1-7 41-01 4 -79 0 30 1 30 + 1-8 4 2-2 + -73 4- -65 4- 2-3 4 3-0 40-99 4 -84 1 30 2 30 + 3-6 + 6-0 + -72 4- -70 4 4-7 4 6-1 40-97 4 -71 2 30 3 30 + 5-5 + 8-0 + -70 4- -69 + 7-1 40-95 3 30 4 30 4 6-9 + 12-8 4- -69 4- -70 4 8-9 40-94 4 30 5 30 + 6-1 + -71 4 7-6 40-97 5 30 6 30 0-0 4 -75 0-0 41-01 6 30 7 30 - 61 - 2-3 + -71 + -69 - 7-6 40-97 7 30 8 30 - 6-9 - 3-3 + -69 4- -60 - 8-9 40-94 8 30 9 30 - 5-5 - 5-4 + -70 4- -61 - 7-1 - 5-1 40-95 4 -77 9 30 10 30 - 3-6 - 2-6 4- '72 4- -70 - 4-7 - 2-6 40-97 4 -86 10 30 11 30 - 1-8 + 0-7 + -73 4- -53 - 2-3 - 11 40-99 4 -63 11 30 134 MR. LUBBOCK ON THE TIDES Table XXV. (*.) Showing the Diurnal Inequality in the Interval and in the Height of High Water for the first six months of the year, for the Moon’s Transit B, p.m. See Plate III. Apparent Solar Time of Moon’s Transit B. January. February. March. Apparent Solar Time of Moon’s Transit B. d -v^. d h. d i/-. d h. d i]/. d h. Observation. Observation. Observation. Observation. Observation. Observation. P M. h m m feet. m feet. m feet. h m 0 30 + 2-3 + •05 + 3-2 + •05 + 3-2 — •09 0 30 1 30 + 3’2 + •05 + 2-8 •10 + 2-5 — •08 1 30 2 30 + 3-2 + •02 + 3-0 — •05 + 1-4 — •15 2 30 3 30 + 3-3 •00 + 2-5 — •10 + 21 — •16 3 30 4 30 + 4-9 •00 + 3-5 — •08 + 1-6 — •17 4 30 5 30 + 60 + •05 + 41 — •03 + 1-2 — •22 5 30 6 30 + 51 + •05 + 1-6 — •06 0-9 — •23 6 30 7 30 + 2-0 + •06 + 0-6 — •17 _ 1-8 _ •36 7 30 8 30 + 0-2 •02 0-4 — •22 1-7 •32 8 30 9 30 0-7 — •11 — 1-5 — •16 — 2-7 _ •17 9 30 10 30 — 0-9 — •15 _ 2-7 — •20 — 2-5 — •08 10 30 11 30 — 1-0 — •07 — 2-9 — •06 - 2-2 — •04 11 30 April. May. June. 0 30 + 1-9 •08 + 0-6 •10 0-8 _ _ •14 0 30 1 30 + 1-2 — •05 0-0 — •11 — 1-4 •08 1 30 2 30 + 0-8 — •18 — 11 _ •15 — 2-6 •15 2 30 3 30 0-5 — •20 30 _ •23 4-3 •15 3 30 4 30 — 2-0 — •28 — 4-2 — •30 — 4-6 •15 4 30 5 30 — 3-3 — •31 — 7-0 — •40 _ 7-8 — •23 5 30 6 30 — 4-7 — •34 — 5-3 _ •35 — 5-9 •17 6 30 7 30 — 4-2 — •40 — 50 _ •30 _ 4-9 •12 7 30 8 30 — 2-7 — •30 — 3-8 _ •21 — 1-7 •05 8 30 9 30 _ 3-4 _ •13 _ 2-2 _ •09 — 11 •04 9 30 10 30 — 2-9 _ •08 — 1-5 — •03 _ 0-4 + ■04 10 30 11 30 — 2-3 — •03 — 2-2 + •01 + 0-5 + •02 11 30 The tide depending on the Moon’s Transit a.m. for the last six months has the same inequality and the same signs as the above ; and in the first six months a.m. and the last six months p.m. the same values obtain, but with a contrary sign. The quantities in the columns headed “ Observation” have been obtained by taking the mean of January and July, February and August, &c., a.m. and p.m., as ex- plained in p. 100. MR. LUBBOCK ON THE TIDES. 135 Table XXVI. Showing- that part of the Diurnal Inequality in the Height of High Water de- pending on the Moon, calculated from the expression d h = B sin 2 S', assuming for Parallax 57', B = 0-5 feet. d h. Moon’s Declina- tion. Moon’s Horizontal Parallax. 54'. 55'. 57'. 59'. 61'. 3 •04 •05 •05 •06 •06 6 ■09 ■09 •10 •11 •12 9 •13 •14 •15 •17 •18 12 •17 •18 •20 •22 •24 15 •21 •22 •25 •27 •30 18 •25 •26 •29 •32 •35 21 •28 •30 •33 •37 •40 24 •31 •33 •37 •40 •44 27 •34 •36 •40 •44 •48 30 •37 •39 •43 •47 •51 For Moon’s Upper Transit the correction in the above Table has the same sign as the Declination. For the Lower Transit it has a contrary sign. This Table was originally calculated for an hourly variation of 1 >li < ■M- ' ... "T Heights of High Water in Mag 18’dG — See Table. XXX/ 3 na rim.- Mlirrr <«vn /•/., .;> / 5f "n" 4/ ’ 7’ * ' > /* -4 k t ll n t li t li \.L V | I’ll nr Truneitx A. A MimrUum ixmnntal. ) tut dare marks*! A.A M | by ertn numhinr The Mo- hi. i iinluniiii.il is north fttun Mag r: *A*> Mag :n',‘ The llnghi.i ixtnunl tig ilia .same Title ./>>• »•.«/»*/ ••••>/• ■' • MR. LUBBOCK ON THE TIDES 137 Table XXXI. Observations of High Water in May 1 836. Date. Plymouth. Portsmouth, London Docks. Pembroke. Liverpool. Salthouse Dock. Leith. Time. Height. Time. Height. Time. Height. Time. Height. Time. Height. Time. Height. 1836. h in ft. in. h m ft. in. h m ft. in. h m ft. in. h m ft. in. h m ft. in. May 1. A.M. 5 12 17 io§ 11 28 18 6-9 1 40 22 10 6 20 22 9 11 6 18 5 2 12 16 1 P.M. 5 45 17 7i 11 48 18 11-8 2 10 23 8 6 40 22 9 11 25 18 3 2 24 16 4 2. A.M. 6 5 17 H 2 20 24 2 7 0 22 6 11 50 18 0 2 46 16 4 P.M. 6 22 17 64 0 5 18 3-9 2 45 25 9 7 15 22 6 3 4 16 10 3. A.M. 6 44 17 10i 0 35 18 7-2 2 55 24 3 7 35 22 9 0 5 17 10 3 23 16 2 P.M. 7 6 18 '2i 0 55 19 1*5 3 25 24 4 8 0 22 9 0 30 18 1 3 54 16 8 4. A.M. 7 28 17 6 1 15 19 4-9 3 40 24 2 8 0 23 6 0 50 18 1 4 18 16 ° P.M. 7 54 17 n 1 35 19 0-2 4 0 23 6 8 25 23 0 1 12 17 11 4 43 15 11 5. A.M. 8 13 16 8 1 58 18 1 1-4 4 25 23 5 8 50 21 6 1 26 17 5 5 8 15 0 P.M. 8 22 16 10J 2 30 18 5-2 4 50 22 9 9 10 21 0 2 0 16 0 5 35 15 5 6. A.M. 9 1 15 5J 2 50 18 3-2 5 15 22 11 9 30 20 3 2 20 15 10 6 5 14 0 P.M. 9 32 15 63 3 25 17 5-5 5 35 21 6 10 10 19 6 2 50 14 4 6 27 13 9 7. A.M. 9 56 14 H 3 45 17 2-0 6 10 21 11 10 45 17 5 3 15 14 2 7 0 13 0 P.M. 10 17 15 H 4 30 16 11-0 6 20 20 3 11 10 16 6 3 49 12 9 7 40 13 1 8. A.M. 11 2 13 6| 5 15 16 8-6 7 15 20 10 11 55 16 7 4 29 13 1 8 18 12 5 P.M. 11 37 14 8* 5 45 16 8-7 7 35 19 2 5 6 11 9 9 6 12 4 9. A.M. 6 15 16 1-2 8 35 20 6 12 25 17 6 5 50 13 0 9 30 12 3 P.M. 6 32 13 6* 7 0 16 7-0 9 20 19 0 12 55 17 3 6 40 12 0 10 18 12 7 10. A.M. 12 55 14 10 7 20 16 1-3 10 5 20 8 1 10 17 6 7 16 13 6 10 34 12 7 P.M. 1 47 14 H 8 5 16 9-6 10 30 19 0 2 30 17 6 7 50 12 10 11 28 13 1 11. A.M. 2 19 15 H 8 43 16 57 11 15 20 7 2 55 18 10 8 25 14 7 11 36 13 3 P.M. 2 58 14 ill 9 8 17 47 11 30 20 3 3 45 18 8 8 55 14 5 12. A.M. 3 15 15 10 9 42 16 11-5 4 5 20 0 9 14 15 9 0 10 13 11 P.M. 3 40 15 7i 10 5 17 11-0 12 10 21 6 4 30 20 3 9 42 15 1 0 22 14 7 13. A.M. 3 53 16 3§ 10 20 17 9-0 12 25 21 3 4 50 20 6 9 57 16 0 0 58 14 4 P.M. 4 23 16 0 10 46 17 9-5 1 0 21 8 5 10 20 3 10 16 15 7 1 2 14 8 14. A.M. 4 43 16 4 10 55 17 6-0 1 10 21 6 5 30 20 6 10 34 16 0 1 32 14 7 P.M. 5 2 16 3| 11 15 17 9-8 1 25 22 3 5 30 21 0 10 48 15 9 1 38 14 9 15. A.M. 5 19 16 3 11 32 17 3-5 1 45 21 11 5 45 20 10 11 10 16 1 1 55 14 10 P.M. 5 28 16 4* 11 51 17 11-2 2 10 22 1 6 10 20 11 11 24 16 0 2 12 15 0 16. A.M. 5 47 16 2 2 20 22 1 6 35 20 6 11 45 15 10 2 29 14 11 P.M. 6 4 16 6$ 0 14 17 6-2 2 45 22 4 6 45 20 10 11 58 15 10 2 57 14 7 17. A.M. 6 26 16 0 0 24 17 87 3 5 22 0 7 15 20 3 3 13 14 4 P.M. 6 35 16 5 0 39 17 2-8 3 15 22 0 7 35 20 3 0 16 15 2 3 32 14 5 18. A.M. 6 47 15 8| 0 58 17 5-3 3 30 21 8 7 50 19 8 0 30 15 6 3 50 14 2 ‘ P.M. 7 4 16 4 1 20 17 4-5 O 50 21 8 8 0 20 0 0 46 14 9 4 10 13 8 19. A.M. 7 31 15 7f 1 35 17 5-0 4 10 22 0 8 25 19 8 1 4 14 10 4 20 13 7 P.M. 7 36 16 0 1 50 16 113 4 20 21 2 8 35 20 0 1 22 14 3 4 38 13 7 20. A.M. 7 53 15 0J 2 0 17 0-5 4 35 20 11 8 45 19 6 1 35 14 6 4 58 13 5 P.M. 8 1 15 9! 2 20 16 11-3 4 45 20 9 9 0 18 6 2 0 13 6 5 26 13 1 21. A.M. 8 36 14 8* 2 37 17 0-0 5 10 20 9 9 30 17 11 2 15 13 8 5 41 13 1 P.M. 8 45 15 6 3 0 17 1-6 5 15 20 8 9 45 17 6 2 40 12 6 6 8 12 6 22. A.M. 9 6 13 10* 3 14 16 10 5 55 20 1 10 10 17 6 3 0 12 11 6 37 12 3 P.M. 9 29 15 1 3 30 16 4-5 6 0 19 2 10 30 17 0 3 19 11 6 7 5 12 1 23. A.M. 9 53 13 104 3 56 15 9-8 6 35 19 11 11 0 16 0 3 50 11 9 7 36 11 9 P. M. 10 36 14 8* 4 27 16 9-8 7 0 19 4 11 25 16 3 4 15 10 3 8 14 11 8 24. A.M. 11 2 13 6 5 18 16 7-5 7 35 20 0 4 55 11 3 8 36 11 4 P.M. 11 48 14 3 5 43 16 7-0 7 55 18 4 12 15 16 6 5 40 11 0 9 13 11 9 25. A.M. ... 6 18 15 51 8 55 19 4 12 35 16 10 6 20 12 0 9 53 12 1 P.M. 0 34 13 H 6 50 16 8-2 9 20 19 2 1 30 16 8 7 0 11 10 10 16 12 4 26. A.M. 1 8 14 9* 7 40 15 10-5 10 10 20 8 1 55 17 10 7 20 12 10 10 46 12 5 P.M. 1 44 14 7k 8 12 16 2-0 10 45 19 9 2 30 18 0 7 58 13 6 11 13 13 0 27. A.M. 2 16 15 44 8 38 16 4-0 11 20 20 10 3 10 19 0 8 28 14 1 11 33 13 5 P.M. 2 49 15 94 9 5 17 8-0 11 35 20 7 3 40 19 6 8 46 15 1 28. A.M. 3 6 16 9 21 17 4-6 3 50 20 6 9 11 15 10 0 5 14 2 P.M. 3 37 16 7| 9 56 18 5-1 12 ’5 21 7 4 20 21 0 9 35 16 6 0 27 14 6 29. A.M. 4 0 16 114 10 12 18 0-2 12 20 21 10 4 45 21 0 9 55 16 8 0 52 14 11 P.M. 4 27 17 14 10 37 18 8-5 12 50 22 11 4 45 22 0 10 16 17 7 1 17 15 4 30. A.M. 4 47 17 34 11 4 18 5-2 1 10 22 3 5 10 22 3 10 40 17 10 1 34 15 11 P.M. 5 26 17 10| 11 23 19 4-6 1 35 23 3 5 45 22 10 11 0 18 1 2 8 16 4 31. A.M. 5 42 17 10 11 42 18 9-5 1 50 23 3 6 10 23 0 11 23 18 6 2 24 16 5 P.M. 6 5 18 34 2 20 23 8 6 40 23 4 11 45 18 9 2 58 16 11 MDCCCXXXVII. T 138 MR. LUBBOCK ON THE TIDES. Index to the Tables. Results deduced from Observations made at Liverpool. These observations were made at Liverpool by Mr. Hutchinson, Dockmaster at that place : they are now in the possession of the Liverpool Lyceum, and they were granted with the greatest kindness and liberality to the author for the purposes of this inquiry by the Committee of that Institution. The intervals in Tables I. II. IV. V. and VI. should be increased by 36 hours to give the real interval between the moon’s transit A and the time of high water. I have concluded that Mr. Hutchinson’s observations are given in apparent solar time. Table I. (a.), showing the Interval between the Apparent Solar Time of the Moon’s Transit and the Time of High Water, and the Height of High Water at the Liverpool Docks, corresponding to the Apparent Solar Time of the Moon’s Transit A in each month of the year, from 13,391 observations made at the Liverpool Docks, between the 1st of January 1774 and the 31st of December 1792. Table II. (b.) (Interpolated from Table I.), showing the Interval between the Ap- parent Solar Time of the Moon’s Transit A, and the Time of High Water at the Liverpool Docks for each month in the year. Table III. (c.) (Interpolated from Table I.), showing the Height of High Water at the Liverpool Docks, corresponding to the Apparent Solar Time of the Moon’s Transit A, in each month of the year. Table IV. ( d .), showing the Interval between the Apparent Solar Time of the Moon’s Transit and the Time of High Water at the Liverpool Docks, corresponding to the Apparent Solar Time of the Moon’s Transit A, for every minute of her Horizontal Parallax. Table V. (e.), Interpolated from Table IV., and reduced to Moon’s Declination 15e. Table VI. (f), showing the Interval between the Apparent Solar Time of the Moon’s Transit and the Time of High Water, and the Height of High Water at the Liverpool Docks, corresponding to the Apparent Solar Time of the Moon’s Upper and Lower Transit A, a.m. and p.m. Table VII. ( g .), showing the Diurnal Inequality at Liverpool, or the Difference in the Interval between the Apparent Solar Time of the Moon’s Transit and the Time of High Water, and the Interval in Table II., and the Difference between the Height of High Water and the Height in Table III. Table VIII. ( h .), showing a Comparison between the Semimenstrual Correction at Liverpool in the Interval and in the Height, as deduced from theory and from the results of observation contained in Tables IL and III. Table IX. (i), showing the Calendar-month Inequality in the Interval and in the Height of High Water, as deduced from Bernoulli’s theory and from the results of observation contained in Tables II. and III. See Plate I. Table X. (j.), showing the Moon’s Parallax Inequality in the Interval and in the ME. LUBBOCK ON THE TIDES. 139 Height of High Water, as deduced from Bernoulli’s theory and from the results of observation contained in Table V. See Plate II. Table XI. (&.), showing the Diurnal Inequality in the Interval and in the Height for the first six months of the year for the Moon’s Transit A, p.m. See Plate III. Table XII. (/.), showing the Interval and Height of High Water at the Liverpool Docks, with the Sun’s and Moon’s Declinations, and the Moon’s Horizontal Parallax (for the mean of all the Moon’s Transits A occurring between 0h and lh) for every year from 1774 to 1792. Table XIII. (m.), interpolated from Table XII. by reducing each quantity to Moon’s Transit A (O’1 30m), and correcting the quantities for deviation from mean Declinations and Parallax. Table XIV. ( n .), showing the Establishment of the Port of Liverpool obtained from Table XIII. by altering the argument from Transit A to Transit D, and reducing it to 0h 0m from 0h 30m. Moon’s Hor. Par. bj', and Decl. 15°. Results deduced from Observations made at London. These observations were made at the London Docks under the direction of the late Mr. Peirse, and they are now in the possession of the Royal Society. The intervals in Tables XV. XVI. XVIII. XIX. and XX. must be increased by 48 hours to give the real interval between the moon’s transit B and the time of high water. I have concluded that these observations are given in mean solar time. Table XV. (a.), showing the Interval between the Apparent Solar Time of the Moon’s Transit and the Time of High Water, and the Height of High Water at the London Docks, corresponding to the Apparent Solar Time of the Moon’s Transit B in each month of the year, from 24,592 observations made at the London Docks, between the 1st of September 1801 and the 31st of August 1836. Table XVI. (b.) (Interpolated from Table XV.), showing the Interval between the Apparent Solar Time of the Moon’s Transit B, and the Time of High Water at the London Docks for each month in the year. Table XVII. (c.) (Interpolated from Table XV.), showing the Height of High Water at the London Docks, corresponding to the Apparent Solar Time of the Moon’s Transit B, in each month of the year. Table XVIII. (d.), showing the Interval between the Apparent Solar Time of the Moon’s Transit and the Time of High Water at the London Docks, corresponding to the Apparent Solar Time of the Moon’s Transit B, for every minute of her Horizontal Parallax. Table XIX. (e.), Interpolated from Table XVIII. Table XX. (/.), showing the Interval between the Apparent Solar Time of the Moons Transit and the Time of High Water, and the Height of High Water at the London Docks, corresponding to the Apparent Solar Time of the Moon’s Transit B, a.m. and p.m. 140 MR. LUBBOCK ON THE TIDES. Table XXI. ( g .), showing the Diurnal Inequality at London, or the Difference in the Interval between the Apparent Solar Time of the Moon’s Transit and the Time of High Water, and the Interval in Table XVI., and the Difference between the Height of High Water and the Height in Table XVII. Table XXII. (h.), showing a Comparison between the Semimenstrual Inequality at London in the Interval and in the Height, as deduced from theory and from the results of observation contained in Tables XVI. and XVII. Table XXIII. (/.), showing the Calendar- month Inequality in the Interval and in the Height of High Water, as deduced from Bernoulli’s theory and from the results of observation contained in Tables XVI. and XVII. See Plate I. Table XXIV. (j.), showing the Moon’s Parallax Inequality in the Interval and in the Height of High Water, as deduced from Bernoulli’s theory and from the results of observation contained in Table XIX. See Plate II. Table XXV. (&.), showing the Diurnal Inequality in the Interval and in the Height of High Water for the first six months of the year, for the Moon’s Transit B, p.m. See Plate III. As the London discussion contained in this paper has been made with reference to transit B, and the discussion of the Liverpool observations has been made with re- ference to transit A, it was necessary to pay attention to this circumstance in the comparisons on the Plates. This has been done for the present roughly, by placing the London corrections more to the left by half an hour. The interval corrections would strictly require, in extreme cases, a slight alteration, which may be obtained from Tables XXIII. XXV. and XXVII., given in a former paper*. Table XXVI., showing that part of the Diurnal Inequality in the Height of High Water depending on the Moon, calculated from the expression d h — B sin 2 l', as- suming for Parallax 57', B = 0‘5 feet. Table XXVII. contains the part of the Diurnal Inequality in the Height depending upon the Sun’s Declination, calculated from the expression {A) B sin 2 § cos

' = 0, MU. MURPHY ON THE ANALYSIS OF THE ROOTS OF EQUATIONS. 167 and therefore 5 3 _ _ 2 a ? 2 _ A ? _ (±* _ 2 i if* it will follow that

is the same as A %l + B, putting /2 a2 2 b\ A = - It - t } a b Hence B = c — P (Ii) •

xi + xa 4- y = - (*2 4- % + y), therefore the equation, of which the roots are xi 4 x2 + Xl + 45 + y> xi 4 x± 4 y, — {x3 4- x4 4- y), &c. is one of six dimensions, but without terms involving the odd powers of the unknown quantity, and therefore these quantities are the square roots of the roots of a cubic equation. Put therefore xi + ^2 4 I" = 2 4 a 4i 4" x3 4- y = 2 4 (3 + x4 4 y = 2 4 y, therefore 3 CL 2 X{ 4- (#1 4- x2 4 x3 4 a?4) 4- -y = 2 ( 4 a 4- + 4 y), ‘£i= — y4 4a-}-4/£>4'4y, the quantities a, |3, y being the roots of a cubic equation, are of the form a — a1 4" J ft 4 \/ ft' j8 = a' 4-^\/(3' + y = a' + ^2^/(3' 4 (3", MR. MURPHY ON THE ANALYSIS OP THE ROOTS OF EQUATIONS. 169 when 6, 62 are the imaginary cube roots of unity, and (3 (3" being the roots of a qua- dratic are of the forms f 3 ' = a" -f v' oi"' (3 Set!". The three other roots of the biquadratic are x2 = 2 S a — (^ + -|-) = — + v' a — S (3 — S y x3 = 2 S(3 — 4 |~) = — — v' a + S (3 — S y xi — 2 ^ y — («i + y) = — - j - -/a — /3 + ✓ y. The constituent or essentially different parts of the roots are a', a", a"', which we proceed to analyse by the conditions of their evanescence. 25. Suppose a!" = 0, then by art. 23 two of the roots of the cubic are equal, or (3 — y, from whence we have x3 = x4, therefore x3 — x4 is a factor of a'", and forming all the other symmetrical factors, we have a'" =: k (a?j — x2)2 Oj - x3)2 (x4 - x4)2 (x2 — x3)2 (x2 — x4)2 (x3 — x4)2, k being a numerical multiplier. 26. Next suppose a" = 0, then by the properties of the roots of the cubic already demonstrated we have 2 « = (3 + y, or a — (3 = y — a, whence ( */ a + S 8) (S a — S (3) = (S y -j- S «) (V y — ,) (x2 — Xi) ■ The two remaining symmetrical factors are fa — x2) (a?3 — x4) + (xx — j?4) (a?3 — x2) fa — a?3) fa “ a?2) + (®i — *2) (a?4 ~ *3) 5 and a" is the product of all three multiplied by a numerical factor k'. 2/. Again, suppose a! = 0, then by the article above referred toa + /3-j-y = 0; but /3 + 7 = — *2)2 4 (% “ ah)2 « 4 7 = (^1 — ^3)2 4 (*2 ~ x^ a (3 — (xx #4)“ 4 Cx2 *3)2, the sum of which being per se symmetrical, shows that a! has no other but a nume- rical factor ; therefore a! - k" {(a?j — x2)2 + fa — x?)2 + (xx - x4)2 + fa — x3)2 + fa — x4)2 + fa — .r4)2}. MDCCCXXXVII. Z 170 MR. MURPHY ON THE ANALYSIS OF THE ROOTS OF EQUATIONS. values ai ready 28. The numbers k, k', k" may be found by the of a cubic, by which we have « = «' + + \/ ia" V' tt") "b \/ (&" — V' to'")} + / {a! + 6 Z/ {to!1 + s/ «"') + G2 s/ (to." — s a!")} -| - */ {ot! Q2 («" -J- a/ a!") -j- 6 \/ (a" — */ a"’)}, where 6, G2 are the imaginary cube roots of unity, then the condition a!" — 0 denotes the existence of two equal roots in the proposed equation. The condition a" = 0 denotes the following relation of the roots Oi ff4) (x2 — %) + (a?i - %) (x2 — xi) = °- The system of coexisting conditions a!' = 0, a"1 = 0 are necessary and sufficient for the existence of three equal roots. The condition a' = 0 denotes the following relation of the roots, 2 (aq — x 2)2 = 0. The simultaneous system of conditions u! = 0, a" = 0, od" — 0 essentially and suffi- ciently express the coexistence of four equal roots. The rational part of the root — only vanishes with the sum of the roots. 34. We now proceed to determine the constituent parts of the roots of equations of the fifth degree by the conditions of their evanescence. 6, G2 represent the imaginary cube roots of unity. co, co2, to2, a4 the imaginary fifth roots of unity. aq, x2, x3, x4, x5 are the five roots of the proposed equation of the fifth degree, viz. x5 -j- a xA -j- h x3 -f- c x2 + d x -f- e — 0. xi = — j + \/ to -\- \/ /3 + v^ y ^ x2 = — ~ co \J a -f- co2 \/ (3 -j -a3 \f y co4 \/ h x3 = — co2 \/ a -J- co4 \/ ft -\ - m \/ y + co2 & MR. MURPHY ON THE ANALYSIS OF THE ROOTS OF EQUATIONS. 173 x4 = — -T + s/ a + co ^ -f - co4 \/ y + <«2 \/ & #5 — r- + a/4 \/ a -f- co3 \/ -j- co2 ^ / y + co § ; the formulae for x3, x4, x5, x1 are derived from the formula for x2, by writing succes- sively co2, co3, &>4, cu° instead of co. oc — oc! -j- \/ (3r -j- \/ y1 -f- \/ h1 (d — oc! -j- \/ j3' — \/ y' — \/ V y — a! — v' (3; -j~ V y' — V § = a! — V (3r — v' y' + s/ cf, such being the forms of the roots of a biquadratic. Again, the expressions for (3', y', h' as roots of a cubic, are p = a” + y p" + 4/ r" y = cc" + 6 4/ (3" + IP 4/ y" i1 = <*" + p 4/ ,3" + 6 4/ y. Lastly, |3", y" as roots of a quadratic, are expressed by the following formulae : (. 3 " = oc!" + y' aIV y" = a"1 — «1V. The quantities — j, u', a", a'", alv are the constituent or essentially distinct parts of the roots xx, x2, x3, x4, x5, and the analysis of their formation is to be sought by observing all the conditions under which each may vanish. 35. If for - y we put -- + x3 it is obvious that the system of five equations for the roots is equivalent to one of only four, viz. 5 \/ a = x4 -{- aft x2 + ^ Xz -f co2 XA -f- co x3 5 (3 = xx + co3 x2 -f- co x3 -j- , and the number of pairs being six, the whole number of factors of «lT is sixty, these factors are very easily formed, and here we present the first thirty factors, the remaining thirty being formed merely by changing the signs of these, or, which is the same, inverting the order of the differences of the roots in each factor. 37. For greater clearness we shall subdivide these thirty factors into five groups, from the first of which xx is excluded, from the second x2, and so on ; each subdivi- sion contains six factors, four of which are of one form, and two of a different form ; they are as follow : O2 — X4) + (x3 — x4) -f co2 (x3 — x3) Os - X2) + " Os — Xi) + »2 Os - xi) 04 — Xo) + » O2 — •%) + O2 — *3) 05 - X3) + a 04 — •%) + 04 — X2) (x2 ~ <%) + (»2 + co3) Os — *4) Os — x4) + 02 + *>3) Os — xz) Oi — ^4) + ® Os - xd + Os - xs) Os — x&) + a (x4 — xb) + co2 (x4 — xx) (x4 — x3) + a Ol — X3) + or Ol — x5) Os - a?j) + a 03 — *1) + "2 O3 — *4) Oi — ^3) + O2 + ^3) Os ~ *4) Os - Xi) + O2 + "3) O3 - x\) 01 — xi) + ” 04 — x2) + ^ O4 - %») 02 — ®s) + » Oi — *5) + Oi — xd (x4 — x4)-{-A> (x5 — x4) + A)2 Os — xi) 05 ~ *4) + M O2 ~ *4) + "2 O2 — *1) Oi — •%) 4- 02 4- *»3) 04 — xz) (x4 — X2) 4- O2 + CO3) Os — xx) 01 - Xb) + * Os - Xb) + ^ ( X3 - X2 ) 02 — X3) -f M O5 — ^3) + *>2 O5 ~ ^1) 03 - xx) + u (x2 — x{) 4- v2 O2 “ *5) 05 — X2) + co Oi — #2) + 131/2 Ol — xi) Oi — x2) 4- O2 4- co3) 03 — <%) • Os ~ Xb) + ("2 + "3) O2 ~ *l) • (l.)J (2.) ! (3.) I (4.) (5.) (6-)J >(A.) (10 (2.) (3.) (4.) (5.) (60 J (l.)1 (2.) (3.) (40 (5.) (60 J (101 (2.) (3.) (4.) (5.) (6.)J >(B.) KC.) }(D.) MR. MURPHY ON THE ANALYSIS OF THE ROOTS OF EQUATIONS. 175 OO 1 (2.) j (3.) ' (4.) (5.) (6.) HE.) (Xi - x3) + (x2 — x3) + CO2 (x2 — x4) . . (x2 — x4) + CO (x4 — x4) + co2 (x4 — x3) . . (x3 — X4) + a (x4 — x4) + a2 (x4 — x2) . . (x4 - x2) -f 2\/ &) e4 — ~ co2 (co - 1) ^ ft ' — cy4 -y/ d4 = co2 (co — 1) (n/ 7 — co3 })) Di = e4 = w4(w_ i) (s/ y — cy4 ^ e)) e2 = 1 1 “ "CO 1 - co3^/l) B co (co 5 (x/ a - \/ 7) ^4 — w (co — 1) ^ K ~ ^ 4 = (V- J j U7 a - *2 \/ y) a — co n + 1] p = (x+ A)n + 1 jV'] p x = [(a? -f- A)”] x = x {x + A)71. MR. MURPHY ON THE THEORY OF ANALYTICAL OPERATIONS. 181 But [xn] a p = [a /] \|/ = « ( x h)n [xn] p a = [{x + hy\ a = a (x + A)". in the latter case the order of the operations is indifferent, because the operation p does not act on the multiplier a , and for the contrary reason the order of x p is fixed. in the first case. Operations are therefore relatively fixed or free ; in the first case a change in the order in which they are to be performed would affect the result, in the second case it would not do so. In a compound operation any part of the symbols may be taken conjointly with the subject in the square brackets, their result being the subject for the compound operation of the remaining symbols. Thus o2] a p A dx = [ax2] ^ A dx. §2. 4. Linear operations in analysis are those of which the action on any subject is made up by the several actions on the parts, connected by the sign + or — , of which the subject is composed. Let p denote the operation of multiplying by a quantity p , then [a + b] p = [a] p + [ b ] p ; this operation is therefore linear. Let p denote the operation of changing x into x + h, then if / (a?), p (x) be any functions of x, we have [/» +

. (HI.) In the expansion (II.) put n h = k, or n — : therefore /M-*)=/« +*£/(*) + • (ilVw + ^-^r1 • (i)/WAc. Now suppose n to increase infinitely, h remaining constant, the quantity h, which a is the increment of x, diminishes infinitely, and the operation in the limiting state when h vanishes, becomes dx. Hence 7,2 7.3 /(* + *) =/ (*) + * dJ (*) + 172 d?f (*) + 17773 ^3/ (*) + 7 &e. • (IV.) The expansions (II.) (IV.) are Taylor’s theorems for the development of functions by means of their finite differences and their differential coefficients respectively. Again, if h be written for h in the expansion (IV.), and the subject be omitted, it becomes ;,2 (] 2 7,3 (l 3 4 = 1 +hdx + +, &c (V.) and Tfi d ® d ^ §3. 7- The expansion given for the operation \p, of changing x into x + h, possesses remarkable properties, which we propose to develop in the present section, from the importance of the theorem of Taylor, which it expresses. Representing, as usual, by 4 the operation of changing x into x -j- h, and by \p' that of changing x into x-\-h' , the quantities h, h' being independent of x, and, lastly, denoting by 4/ the operation which changes x into x + h + h', we have obviously the identity 4 4' = v, ; 184 MR. MURPHY ON THE THEORY OF ANALYTICAL OPERATIONS. and putting for these symbols their expansions found in the preceding article, we get c.}{ m d -2 m d s 1+h'd* + \%+Hks+>*us •} — 1 + (A + h') dx -j- {h + hJf dj2 (h + h')3 d3 1 . 2 + 1.2.3 -j-, &C. a relation which may be verified by actually compounding the two polynomials of the first member. Now in this act of verification the operations h dx h! dx have only such properties as are common to any two linear operations which are relatively free : hence if 0, 0r represent any such operations, we have generally f 62 63 „ 1 f , S'2 | 1 + 0 + J~o “f“ 1.2.3 + > &c* j • | 1 4- 0 + + j o ,5 +5 &C. — 1 + (0 + 0 ) i fTo- + 1.2.3* and it is easy to extend an identity exactly similar to any number of operations which QII2 QII3 are all relatively free ; for in introducing a new polynomial, I + 0" + — -J- y-^-|--,&c\, we have only to regard 0 + 0' as itself a free linear operation, and therefore the result would be 1 + (#+#+^+«±^ + a±j^+J&e. 8. If the subject be a function of two variables, x and y, then using to denote that x must be changed into x + h, and \py that y must become y k, these opera- tions are relatively free, it being of no consequence which operation is first performed ; therefore the operations A^, Ay of taking the corresponding finite differences are also free ; from whence, lastly, the differentiations relative to x and y, represented by dx, dy , must be of the same character. Now since and 7,2 d 2 h3 d 3 , , , , , , l‘‘>V , EAl , . therefore, by the general identity of (7-), we have W,= \ + (hd, + k d,) + (AsL+lM + y + k-M +> &c. And now introducing the subject f(x,y ), and expanding the terms in the right member of this identity by the formula given in the preceding section, it will be- come, in the common notation, MR. MURPHY ON THE THEORY OF ANALYTICAL OPERATIONS. 185 /(, + + *) ^ ^ + eqp . T^s +.*«. d2f(x,y) F d3f{x,y) hlc1 dy 2 ' 1.2 “l- dx dy2 ' 1.2 -,-, The properties of this series when any way involved are common, as has been seen, to those in a series where 0, any linear operation, is put for n, and therefore we may write the purely symbolical identity 6 02 03 £ = l + 0 + 772 ~b 77777 “K &c.. where 0 may be an imaginary multiplier, or any species of linear operation. Thus if 0 — h dx and denote the operation of changing x into x + h, we have Similarly J. _ &hdx ~ X 4y = ikdy 4x4y — c(hdx + kdv) all of which are proved by the formulae of art. 8. 1 1 . Having seen in the course of the investigations of this section the signification of the indices of operations when fractional negative or even purely symbolical of linear operations, it is easy to prove by similar steps that in all cases where 0, (? are relatively free. (0 + 0)n = P + nf~l ff + n (n — l' . 0n 0'2 +, &C. ; ] . 2 MR. MURPHY ON THE THEORY OF ANALYTICAL OPERATIONS. 187 for since {0 + 0)n (0 + 0')m = (0 + 0')n + m, it follows that the composition of the polynomials j> + V+,8tc.|.|r+)«r-V+^^-).■ . f + " - g iP, &c. ; and since nothing- in the actual verification of this identity depends on their being integers, for which case the expansion has been proved, the identity holds generally, and therefore if m = n, and we take p , such polynomials, we have ^(r^n^-l0'+^Y^-.0n-20,2 + .. y=0nP+np0np~1 0' + .0np~2 0'2 §^0n n0n~X 0' + j- ? — 0nq nq§iq~l 0' &c. Put w = y, q q j ^ {d' + j .o7’ "' + + or -1-2- X- i ~ *) /X - 2\ («+«,)?=oi’ d'+ ■-.Ap y^+&c. Again, since | Id'+^y^ where

4* x denoting the operation of chan- ging x into x + h : hence [/’(«/)] = 0. Then if X be any function of x, and | be any particular value of [X] A”1, we shall have more generally [X] A~l = i + f(y ), MR. MURPHY ON THE THEORY OF ANALYTICAL OPERATIONS. 189 which includes the former; since, the form of f{y) being arbitrary, we have g alone, amongst the infinite number of values of In compound operations, the appendage obtained by the first simple operation be- comes a new subject for the succeeding operations, each of which may in like man- ner introduce a new appendage. 14. The operation ypx, taken directly or inversely, is incapable of introducing any appendage : for suppose [0] -p ~l =

(x + h) =

x> then considering 6r as a sub- ject, put \0~\ \LV = 0[v, and if the compound operation [u] 0x\px be proposed, its value by transmutation is \ii\ \px 6' x, for in the first compound operation ^x affects all the preceding symbols as forming its subject. Again, let jV] 6X Ax = y be proposed for transmutation, we have y - |>] 6X (Ar - 1) = M Wr and putting Ar + 1 for ^x, and 6X Ax for the finite difference of 0x considered as one operation, we have y = [u] (At &x + 0x Ax) = [w] 6X Ax. Lastly, divide this identity by h , and then put h = 0. When -j becomes dx, and d’x becomes &x, we get for the transmutation of 6X clx, M K dr — M (dv K + K dJ- These formulae of transmutation separated from the subject are respectively 0 -A — \L/ 0 \L/ X T x T X X ~ X 0 A = A which gives K dx = W • dy p' (x) = 0X dy p' (x), . . . n dp (x) where ©' («r) is written for — This example shows how operations may themselves be the subjects of other ope- rations. 16. We now proceed to consider the transformed values of 0X 4>nx, A Anx, 0v dnx, when n is any positive integer. First, K X = X ^ X = 5 suppose therefore 0 d ^ — (7) d d © d • a: t i ~x * x x > x t x Now px$x regards px solely as the subject of the operation 4*) and $ d d zn d $ d d X • X I X *X XIX • X by the first formula ; therefore A'x X = ^2* ^ 4V and in general if we suppose then but K = ’L*-1 f.”-1 = t*> 0 ’ll/ n — © d = d © d : X Ti ra; Yx Yx T x Yx 5 0 d W_1 d =J/ 1 “i tj: "a; a: < a: by the first formula ; therefore 0 d re = d "-1 d 0 d K = d ” 4 d \ a: i u t# a? ' a: t # # t or 192 MR. MURPHY ON THE THEORY OF ANALYTICAL OPERATIONS. This general formula may be more readily deduced by considering that px is the operation of changing x into x n h, and consequently px may at once be substi- tuted in the first formula for px. Secondly, therefore but 0 A — A 0 p -1- 0 A XX X X • X 1 X x^ 0A2=zA0P A + 0 A A X X X X Tx X 1 X X . ' X ’ 0 ip A — A . 0 p 2 + ^ P A X ‘X X XX *X 11 or T # X * writing ^ px for ^ ; and similarly whence 0 A A = A . 0 p A 0 A 2, XXX X X ‘ X X [ X X } generally suppose 0 A 2 ~ A 2 . 6r P 2 + 2 A . 0 p A + 0 A 2. xx xx ix * a: j? * a: a? ■ xx 0 An~l ~ A71-1 .0 P 71-1 + (n— 1) A n~2 .0 P w"2 A X X X X T X 1 v / J? vx Tx X + (w-l)(»-g) 1 .2 . 0 pn~3 A2. X T X X Now if we write 0X px for 0x in the fundamental formula, we have 0 pm A = A . 0 pm 4- 0 pm~1 A X Tx X X X TX 1 X T X x each term when we put for m, n — 1, n — 2, &c. successively, will thus be divided into two, which being placed in two distinct lines will give K K = a;.?a,+ (*-i)a;-1- w1 A, + .A/-2 -w* a} + &c. + A/-1 . w1 A, + (-^M . A/-2 . = vw+»a;-' -w1 a, + '-44 • a,”-2 • which is the general formula sought for. Divide now by hn and observe that y becomes dx and px becomes unity as a mul- tiplier when h = 0, hence the third general formula ex dx = dx °x + n dx~i * ex dx “5“ 'T72” ' dx~~* • 6x dx + &c- which when 6x represents quantity is the theorem commonly called Leibnitz’s. 17. We next proceed to investigate the formulae for negative indices. First since p~l denotes simply the changing x into x — h, we may write p ~x for px in the first formula. dx ^x 1 = 1 • °x 1 Therefore MR. MURPHY ON THE THEORY OF ANALYTICAL OPERATIONS. 193 more generally Secondly, since therefore 0 4 -* = 4 ~n . 0 4 -»• X ' X i X XiX 0A=A04+0A X X XXIX 1 X X A -1 0T Ar — 0~fl + A 0~A7 X XX XIX6 X XI Put now 0X 4*-1 for 0X, and therefore 0X for 0x $x ; hence therefore A -1 0 4 -1 A = 0 + A -1 . 0 4 _1 A X X TX X X 1 X X T X X 0 A -1 — A -1 .0 4 -1 — A -1 . 0 -A -1 . A . A -1. X X X X ‘X X X T X X X Put 6 1 f°r ®x-> thence we have 0 A -1 — A -1 .0 4 _1 — A ~2 .0 4 “2 A . + A “2 . 0 \L ~2 A 2 . A Vx X x X ' X X X T X X • X X < X X X J or we continue this process indefinitely 0 A ~ 1 = A ~ 1 . 0 4 _1 — A “2 . 0 4 “2 A 4- A ~3 .6 \L ~s A 2 —■ See ux x x x tx x x t x x 6 x x tx x which is the same as the general formula for 0x Ax when n — — 1. Again but and A ~2 = A ~x . 0 -1 . A — A _1 . 0 A -1 A . A “2 X X XIX X X XIX XX* A-1 0 4 -1 . A _1 = A “2 . 0 4 “2 — A “2 . 0 4 -2 A . A -1, X X T x X X XIX X X IX X X 1 Hence A “1 . 0 4 -1 A . A _1 = A “2 . 0 4 -2 A — A “2 . 0 4 ~2 A 2 . A -1. ■X X TX X X X X T x X X X TX X X 0 A “2 = A ~2 . 0 4 “2 — 2 A “2 . 0 4 “2 A . A -1 + A 2 . 0 4 “2 A 2 . A x x x x Tx x x t x x x 1 x X TX “ar a and in a similar manner it is easy to prove generally in a terminating series .! n{n— 1) 0 A A ~n .0 4 ~n - n A ~n,9 4 “B A . A 4- -\-~.0 4 A 2 . A ~2- X 1-1 X VX T X X X T X X X ' 1.21 x ' x X X or in an infinite series, 0 A ~n — A ~n .0 4 -"-wA -(B+1).04 “"(n+1>.A -pn^'V>1~A -(*+2)04”-(’,+2>A 2. X “ X X X T x X X T X X ' 1.2 x XTX ^ X Thirdly, divide Ax by h , and then put h — 0, whence 0x d~l = d~l . 0x — . 0^ dx d~l -l a ,1 -2 7i 7 i .7 -3 ~d-\0~ d~2 .0X4* F . 0r d2 - &c. a? a? a? x x 6 x x x 9 d~n = . 0 - » d ~n . FJ . d ~ * -J- • M? • '2 - &c. a? a? x x x xxx ,3.2 x x x x = . 0, - » £~(w+1) Ml + • i-(n+2) - FF2 ~ &c. a? a? a? j n > j 9 2 x x x which formulae admit of most extensive applications, whether 9X be regarded quantity or a fixed operation. -2 9 - &c. -&c. as a 194 MR. MURPHY ON THE THEORY OF ANALYTICAL OPERATIONS. § 6. 18. Before proceeding further in the search of the fundamental formulae for the transformation of operations, we shall exemplify the theory which precedes by invert- ing binomial operations and applying the results to some simple cases. Let 0, O' denote two linear operations relatively fixed or free, and let us seek the value of (0 — 0')_1- Put (0 - 0')-1 = 0-1 -j- ni ; the latter being the difference of two linear operations must itself be linear. Hence ] = (0-1 + (0 - 0') = i - 0-1 o' + m (0 - &) therefore Similarly put which gives whence so again put m (0 - O') = 0-1 0'. ill = 0_1 0> 0_1 + ni (0 - O') = 0-1 O' - (0-1 O'Y + ^ (0 - O') y2 (0 - O') = (0-1 o')2 ,2=(0-l0')2 0-1 + , 3 = (0_1 O')3 0~ 1 + &c. = &c. We thus obtain (0 - 0')-1 = 0~ 1 + (0-1 O') 0~l + (0-1 O')2 0~l + + (0=1 07-1 0-1 + % where vjn represents the compound operation (0-1 O'f (0 — O')"1. The same formula continued to infinity would be obtained by first putting O'1 (1 — 0-1 0')-1 for (0 — 0')-1 ; and since the operations represented respectively by 1 and 0 1 O' are relatively free, we should have by art. 11. (1 - 0~} O')"1 = 1 + 0-1 O' + (0— 1 O')2 + &c. ad infin. When 0, O' are relatively free the theorem becomes (0 - 0')-1 = 0-1 + 0-2 o' + o~3o'2 -f 0~40'3 -j-.... o-^o"1-1 + 0-n0'n (0 - O')"1. 19. For a first example suppose to denote the finite difference, on the supposi- tion that by the operation 4^ the quantity x is changed into x + h. Then At~j is the finite integral, and in the usual notation of analysts is denoted by 2^, we have therefore [/»] 2*= [/(*)] (^- I)"1 = [/(*)] {V1 + V’ + Vs+-4.-M) + V-2,} = /(* - +/(* — 2 h) +f(x -3 //) + ... +/{« (w — 1) M 4- - nh); MR. MURPHY ON THE THEORY OF ANALYTICAL OPERATIONS. 195 X where it may be remarked that if -j- be an integer, the final terms of the series would be . . ./(2 h ) + /( 0), at any of which, if we suppose the series to stop, its finite difference would be obviously f(x). For the next example suppose the subject to be f(x + y), and that by the opera- tion x receives an increment h, and y the same increment by the operation then it is obvious that [f(x -}- y)~\ (^x — — 0, therefore [f (x + y)\ (Ay — AJ = 0 ; hence fix -J- y) must be included in the general value of [0] (Ay — A/-1. Now [0] (A, - A.)-1 = [0] {Ay-1 + Ay-2 . Ax + Ay-3 A/ + Ay-4 A/ + &C.} and also [0] Ay-1 =

(*) y{y—h) iy-zh) 1 . 2 . 3 . h3 ’ &c. Hence [0] (A, - A,)-1 = p (*) + f • Ap (*) • A2 f (*) + y(y- h) [y - 2 h) l . 2 . 3 . K6 . A3

y-Ax = 0 h 2 D MDCCCXXXVII. 196 MR. MURPHY ON THE THEORY OF ANALYTICAL OPERATIONS. put h — 0 and ^ becomes dx, ^ being similarly dy ; therefore U(xJry)~\ (4 “ dx) = hence f(x y) must be included in the general value of [0] (dy — dx)~]m But [0] (dy — dx)~l = [0] (dy-1 + dy~2 ^ "f ^y^ "f dy" ^ d +, &C.) Now [0] dy-1 -(p (x) an arbitrary function of x ; therefore [0] dy-2 ~ &c. where /' (#) /" (.r), &c. are the successive differential coefficients of f (x) ; this is Taylor’s expansion. If we put f (x) = a and for the limit of an — 1 write log (a), we get from this aJ = 1 + y 1. • (a) + • ( !• • aY +> &c° These examples suffice to show the mode and use of the inversion of binomial ope- rations. 20. To return to the general theory, suppose 0, /, x to represent three operations connected by the equation 0 1 = t x, where the subject is omitted, the identity being supposed general ; the symbol / represents an operation which may be said to be in- termediate to those designed by 0, x. If either of the extreme operations 0, x be given, and the intermediate i be also given, the other extreme may be readily found for 0 = / nr1 and x = i~x 0 /. ! MR. MURPHY ON THE THEORY OF ANALYTICAL OPERATIONS. 197 A remarkable property of intermediate operations is that they are also intermediate between any operations which are the same functions of the extremes. For let 9 i ~ i z then performing the operation z 9 1 z — i z2 put now for t z its equivalent operation 9 1, and we have 92 i = / z2. Similarly if we suppose 9n~1i = izn-1 then but therefore 9n~liz = izn i z — 9 9ni = izn Again, suppose the subject in the last equation to be one on which the opera- tion 9~n has been performed, then that equation becomes / = 9~n i z\ or 9~n i — tz~n. Again, suppose K an operation satisfying the equation n 0m < = ( K. We have by the parts of the proof already given in this article, rtfl V Tl H ( — S l\ = l Z , or Km = zn,K = Zm ; hence n n 9’fii l — i zm . From these premised equations it follows, that if f (9) f (z) represent the aggregates of any similar powers of the operations 9, z , with the same coefficients, we must have generally f(9).i = #/(*). By this theorem, if f (9) be known, / (z) can be found, supposing that we know i the operation intermediate to 9, z. 21. We shall now apply this theorem to cases where 9, t are given, and therefore ^ known, as above shown. Let one extreme 9 represent the operation of differentiating relatively to x, and the intermediate / that of multiplying by zax, then we have dxzax = zaxz 2 d 2 198 MR. MURPHY ON THE THEORY OF ANALYTICAL OPERATIONS. therefore but by § 5. therefore Hence ®x dx — dx °X + °x dX> *-amda = dxr"-ar" = {dm-a) i— d ' — a = z the extreme required. Now if 9 1 = i z, it has been shown that f (6) . i = if («). In this case therefore f (dx). ?* = ?*/ (dx- a) To find the intermediate operation between dx-\-b and dx -f- c; b and c not containing x. Put f (dx) = dx -f- b in the last identity, and b — a = c we then have (dx + b) . z{b~c)x = (dx + c) f(dx + V) . .<»-'>•* = #->*/ (d. + c). 22. Suppose the intermediate operation / to denote s p considered as a multiplier, 'P being a function of x, of which the differential coefficient is P, and 9 to represent dx as before, it is required to find z. Since therefore But Hence Corollary ; j ’p ’p d s = g . z X z =. s p . d . s p. X -'P dx = dx S-'p + F* dx = dm s” p - P a-'p = (dx - P) a-’p * = dx- P. p _ ;p = P). And if VQ be a function, of which Q is the differential coefficient, we have in like manner /w •«'*=« vot- Q)i hence or *'P/K - P) • ^'P = - Q) that is, s'^-p) is the intermediate to the operations dx — P , dx— Q. 23. Let i now signify the operation of changing y into y -f- (x), 6 being, as be- fore, the operation of differentiating relative to x, and the subject being a function of x and y, and '

= i -f(e - d,) - &c., and ' dx = •*'“*> ./(0 - dx also (8 - d.) < = (8 - <*.) N0w 0 — dx is free relative to its own functions, hence therefore f(0-dx) = (9-dx).d~\ from whence i is known. For a second example, suppose ip the operation of changing x into x + h, A that of taking the finite difference on the same hypothesis, 0 any linear operation, then / is required to be such that (4 - 0) i = t A 0. By art. 15, i A = A i \p + / A — ip i t i A — ('P' — t . i ,*P~1) * "4 '• Substituting we obtain ( \p — 0) i — (\p — t . i ,pj~ ■*) i \p 0. To satisfy this identity, suppose i . i ^~l — 9 ; now i 41 is free relative to i, hence I ■pi~1 s — 0, prefix to each side the operation / \p, which only alters the subject, which is perfectly general ; therefore I = i \p . 0 ; hence the preceding supposition fully satisfies ; therefore we have this theorem, if t be determined such that = 0, then shall (4 - 9) i = i A 0, and -»), = ./( A 8). As a particular case, suppose 0 to be a multiplier P^, then i will be another multi- plier vx, such that 202 MR. MURPHY ON THE THEORY OF ANALYTICAL OPERATIONS. or (log vx) -logP., from whence vx or i is determinable. § 8. 27. In this section we shall give some examples of the use of the formulae inves- tigated in the last section. In general dxf = *'(da-a)9 therefore d - a = t~ax diax. X X Put for a in this formula the terms of the series 0, h, 2 h, ... . (n — 1) . h, and com- pound all the binomials which result from these substitutions, hence dm{d-h){d-2h) (d-(n~l)h)=dx^d^\r2kxdjhx g-C*-U^gK- D*. = dx rhx dx rhx dx rhx dx rhx dx &<■ n - dx t~hx — h dy, putting y = z~hx. Now therefore d, {d. - h) (d, - 2 h) .... (d, - (n - 1) h) = 4” . Example. The expansions of ( a -j- b)n, viz. an + n an~l b -j- n — • an~ 2 b 2 +, &c. and i -f n 1. . (a -f b) + +’&c- being identical when n is a quantity, ought to remain so when n is a linear operation, to verify which, suppose n = dx, now it has been shown that [/ (#)] shdx = f (x + h) ; hence [/(^)] (a + b)d * =/{a? + 1. . (a + &)}. But (a + b)dx — adx + dx adx~l b + ^ a ^ . adx 2 b2 - f- y 7^ — — . adx~3 IP -f-> &c. =■-•{' u ■ i +■ ^ ■ (iy + -• w-:^’ .o' +m.} But by this article dx (dx - 1) (dx - 2) . . . (dm - n + 1) = dyn .yn, if y = ? ; dy2 (by'2 1.2’ V a > and now introducing the subject f (x), we get /{* + !••(« + »)} =/ (® + 1. («)) + f + -jr • - | which series, if we substitute for x its value 1. .y, and put f { 1. .y) —

*4 MR. MURPHY ON THE THEORY OP ANALYTICAL OPERATIONS. 203 0 y + ~by) — P (ay)+~ d■ d, = (d, + «,) (<*. + «, + «*) £<-+*>>*. Similarly f1* dxf** dxf** dx = (dx + oq) ( dx + oq + “2) (^* + ai + a2 + “3) g(“1 + ai2+“3)a; ; and generally ^■d^’dx^dx..^‘d=(dI + al){dI+ai + ui)...{dx + al + a2+...+ay-^+----^. If therefore we expand according to the decreasing indices of dx, the compound operation, (dx + «i) {dx + oq + a2) . . . (dx + oq + a2 + • • • + 05 J . 2“'* . s*2* . s“3r . . . &“nX, we shall then have only to put v1 for g*1*, v2 for g®2*, Sec. ^ for a, s®1 ®, ^ for a2 *, &c. dx 1 J d x 1 ’ To effect the composition above indicated, let us seek the product (arranged ac- cording to the powers of x) of (x + oq) (x + oq + «2) (x + oq + «2 + a3) * * • (x + al + a2 + a3 + • • • + «„). MDCCCXXXVII. 2 E 204 MR. MURPHY ON THE THEORY OF ANALYTICAL OPERATIONS. Represent this product by + Ax rf*-1 + A2^-2 + . . . + Am xn~m + . . . + An_1 x + An, the general coefficient Am being the sums of products, each of which contain m factors. For Al it is easily seen that its value is n + ( n — 1) a2 + (n — 2) a3 + . . . 2 an_1 + uH. Again, A2 consists of products such as a1 a2, al a3, a2 a3, &c., and pure powers, as eq2, a22, &c. ; the general form of the first class of terms is ap a , and we now proceed to find its coefficient, or the number of times this combination occurs, which number may be denoted by (xp a ), and supposing p less than q, no factor preceding x -f- eq + a2 + . . . will be concerned in forming the combination in question, and in the factor itself and the succeeding ones the terms preceding a may also be neglected. The factors commencing from the above, arranged horizontally, will form this diagram. x + + • • • + <*p x + ai + • ♦ • + ap + ap + 1 X + al + • • • % + Up + 1 + % + 2 0C + «i + . • • «p + + l + «p + 2 + • • • + % • * ^ + «i + • • • «p + + + a? + 1 x + + • • • % + aq -j- a? + i + aq + 2, &c. &c. Now if a?+1 were placed where the asterisk stands, the combination of ap with aq and a +i would be alike, .*. (ap ag) — (ap a?+1) = the number of combinations of one term at the asterisk with the terms in the vertical column of ap, except that ap which is the same horizontal line with the asterisk ; it is therefore the number of terms minus one in that column which (since p — 1 factors precede the first above written) will be n — p. Therefore A denoting the finite difference, when q increases by unity we have A («p %) — -(n-p); therefore {ap a ) = (n — p) (c — q), c being independent of q. Suppose q — n, (ap un) will be the number of terms minus one in the column of since an enters only once; that is (ap an) — n — p, therefore c — n — 1, or c = n -f 1 which gives (ap %) = (n — p) (n— q + 1). As for the coefficients of the powers as ccp2, denoting such by a similar notation (ap2), they will not be affected by the supposition that oq = 0 a2 = 0 . . . up _ x = 0 oip + j = 0 . . . = 0, MR. MURPHY ON THE THEORY OF ANALYTICAL OPERATIONS. 205 r, r > q, q > p, &c., then by the same process (usaraqap ) = (n — s + 1) (n — r) (n — q- 1) (n—p — 2) Again, if we erase the ap which is in the same horizontal line with ar the number of com- binations of the remaining terms ap (in number n — p) are — — — - and since the number of terms in the vertical line where a stands is n — q + 1, it follows that («p i.2 • (n q ~ J- 1)> and generally (//a9...) \ s t q / _ (n — s + 1) (n — s) ... (s1 times) (n — r) (n — r — I) .. . (r1 times) (n — q — 1) (ti — q — Q) ... g’ times 1.2., 1 .2...H 1 . 2 . . . q1 2 E 2 206 MR. MURPHY ON THE THEORY OF ANALYTICAL OPERATIONS. Lastly (a^3) is the same as if all the terms oq a2 &c. were zero, except ap and is therefore (n —p 4- I ) (n — p) (n — p — 1 ) 1.2.3 (n — p + 1 ) (n — p) ... (p1 times) More generally (ap ) 1.2 . . .p1 We have thus investigated the coefficients of every combination which enter the d P b , whole product, and then if only l be substituted for any general symbol {cxP), the dxP P required development is completely obtained. It may be remarked that the coefficients of the combinations of consecutive terms are pure powers, thus (cq a2) = (n — l)2 a2 a3 = (n — 2)2, &c. oq a2 a3 = (n — 2)3. 29. By the preceding investigation we have obtained the following general formula in which the subject is any function of x : vi • v2 • v3 • • • v, x x v J v2 d, x 1 v ' v3 a x 1 vn a x j + rf/-2{(n- 1)(«- i ,dx d vx d v4 + («- 1) (— »)& & + . / ^ dvn dv o , , d vq dv4 + («-2)(«-V*'^ + ("'2)(,"3)M''vS + + (w „ 3) 0 — 3) — ^ + ... + + n (w— 1 ) d2iq (w — 1) {n — 2) c?av2 2 ‘ vldx‘ + 2 * v2dx2 (n — 2)(n-3) 1 2 * v3dx2 * ' ‘ ’ j + rf ”-3 { (« - a) (- - 2) (« - 2) • +. to. j +, &C. Pat v4 = v2 = v3 = . . . = vn = v hence, 4 d )n = d n v + d n~l vn~l . ^ \ x/ x ' 2 * dx + v n - 2 J (”- l)n(n + 1 )(3”-g) - 2 ^ , ^ \ 2.3.4 dx2 "i" (n — 1) . n (« + 1) 2.3 „ i d2vl ‘v dx*\ MR. MURPHY ON THE THEORY OF ANALYTICAL OPERATIONS. 207 and similarly if we put in the general formula v1 = 1, and write v1 for v2, v2 for v3, &c. and then multiply by vn, finally making all equal to v, we obtain dx (dxvy=d;vn+ + dx n - 2 | (” — 2) (w — 1) w (3 n - 5) J)W _ 2 drf j_ (” - 2) • (» - 1)» a,n - 1 2.3.4 d. + 2.3 d 2_v 1 x1] +,&c. Put now — for v in this formula, whence (dxv-r=d;v (n — 1) . n 2 . dn~l v~n-1 d v dx , /ra-2 f(«-2)(«- l)n{n+ 1) _2dv3 (»-2)(»-])n ,_Ad2v} 0 + dx | 274 dF ~ 2.3 • d75/+’&C- 30. Change of the independent variable. When u is a function of y, and y of x, then it is easily shown that du ~~ ~Toc • ("dl) > ov dy = dx . omitting the subjects; hence by substitu- dy tion in the preceding general formula we have 7 n (dy\~n (i n-l).n x ( dy\ W = d* -Kdi) 2 — • d ■ ■ Xii) f (« — g)(» — i). »(»+!) (dy\-n-'i (£y\ * x 2.4 \dx) \dx V + 5 &C- Thus, for example, if w = 3, dtf and — ft— 1 2 (w— 2).(«— 1) . w (dy\~n 1 d3j ' 2 . 3 ! / dy\ n 1 d?y \d x) ' d x3 J _ d3^ /djA-3 o ( dy\ ~4 d3?/ d?< f / dpv ~5 / d2jA2 /djA~4 Fj/ 1 dxa'\dx/ 'dx2\dx/ ' dx2' d x\_° \dxj \dx V Vdx/ •dx3j ’ d6x_ fdy\~5 ( d2y\ 2 / dj/\ ~4 d3?/ dp \d» 2 . 3 . . . [m — 1) \dx) ' y m— 1,0 (?? + 1) (n + 2) . . . (n + to — 3) / “w“w+2 2. 3... (to — 2) ' \dx) ' ^ m- 2,1 , (« + 1) (» + 2) . . . ( n + to — 4) (dy\ -w-w+3 + S.3...(M-3) • \£) -y«_ M + (g) — n— 1 * *^1, m—2’ m being > 1. Corollary. Put u — x, then l^ = n{n- l)(»-2)...l#n., where xre_l _ (ft + 1) (ft + 2) . . . (2rc — 2) /rfy\ ~2w+1 * Xtx) 2.3... w — 1 Vn- 1,0 (» + 1) (ft + 2) ... (2 ft — 3) 2.3... (»-2) -2 ti+2 Thus ■3>.-%v &c- _ („ _ 1) (n + 1) . . . (2« - 3) . (g)2 + (b - 2) (» - 1) . . . (2 » - 4) (off -y„-z ,>• &c- } • (jf) 2”- *£=f*y7l I (*s\~‘ — (iiY dy dx *^°»° j ’ \dx) \dx) (JY- f2^ v 1 (*yY*—(dyYs d*y dy*~ Y dx'y^]-\dx) -\dx) 'dF $={3.4.g^o-2.3.(^y.,1>I}(g) = 3.(g)‘5. 1 sTi- &c. f 211 ] XIII. On the Adaptation of different Modes of Illuminating Lighthouses ; as depending on their Situations and the Object contemplated in their Erection. By William Henry Barlow, Esq. In a Letter addressed to Peter Barlow, Esq., F.R.S. 8$c., and communicated by Him. Received April 27, — Read May 4, 1837. Constantinople, March 14th, 1837. Having made several experiments with the Drummond light, and other means of illuminating light-houses, undertaken at the request of the Turkish Government, with a view to placing lights at the entrance of the Bosphorus from the Black Sea, I have been led to observe some facts regarding the illuminating powers of the lights themselves, and the increase obtained by the use of reflectors and lenses, which, I trust, may not be found uninteresting. On the increase of illuminating power obtained by Lenses and Reflectors. Let L in the annexed figure represent a lamp ; m, m, two reflectors, which may be so adjusted as to throw the reflected images either in parallel lines on a screen at P' and P", or at such an inclination as to unite with that of the light itself at the centre point P. Let also s s represent a screen of such imperfect transparency as to absorb the same quantity of light in transmission as the mirrors m, m absorb by re- flection; then in the first case the three images P', P, P" will have equal surfaces and intensities*, and the illuminating power will be three times that of the central lamp ; and when by a different adjustment of the mirrors the three images are blended in one, then the surface will be equal to that of the central image, but the intensity three times greater, so that in either case the illuminating power will be proportional to the number of mirrors, or to the surface of those mirrors. If, therefore, we con- ceive the whole space between m, m to be filled with mirrors, to reflect the light in parallel lines on the screen P', P, P", it is clear that the illuminating power of the * We reject here the difference in the length of the trajectory of the direct and reflected light. MDCCCXXXVII. 2 F 212 MR. W. H. BARLOW ON DIFFERENT MODES lens will be expressed by the number of times the surface of the central image is contained in the whole surface of the screen P, P" ; and this is true whether we consider the several images to be thrown in parallel lines, or condensed in a focus, or dispersed over a larger surface, for as the illuminated surface is contracted, the intensity is increased, and as it is extended, the intensity is diminished in the same proportion, so that under all circumstances the product of surface and intensity will be a constant quantity. Hence the illuminating power (abstracting from absorp- tion) will be increased by the reflector in the ratio of the surface of the lights to the surface of the end or section of the reflector. Or in other words, the area of the end of the reflector divided by the area of the light, will be a numerical measure of the illuminating power. This result is obtained by supposing the reflector to be composed of a number of small plane reflectors, each throwing the light in parallel lines, and each image therefore as having the same intensity as the direct light (screened as above) when viewed from the same distance ; but with a continuous curve surface, such as a para- bolic reflector, we must consider the divergency of the emanating ray at the point where it falls on the reflector, which will vary inversely as the square of the distance of that point from the centre of the light, or directly as the square of the sine of half the angle which the light subtends from that point, and therefore as the versed sine of half the same angle ; and the sum of all these must be compared with the area of the reflector, that is of its section or end, which varies also as the versed sine of half the angle which its extreme edge subtends at the light. In order, therefore, to compute the increase of illuminating power due to a para- bolic reflector, according to this principle, we must find a mean focal distance , that is, a distance (from which to estimate the constant angle subtended by the light) that shall be equivalent to the several variable distances. Let A D B be a parabolic reflector and C its focus, then will D C be the minimum and A C the maximum focal distance. Now if the light at C emanated from a point, all the rays intercepted by the surface A D B would be projected forward in parallel lines and cover the plane surface GH = AB at whatever distance it might be placed OF ILLUMINATING LIGHT HOUSES. 213 from the reflector, and the light at G, K, L would be that due to the distances A C, I C, D C respectively : if then a segment of a sphere ni on be described intercepting the same number of rays as ADB, and whose surface is equal to the area of A B or H G, we shall have the same quantity of light equally distributed over the same surface ; hence the radius of the segment mon will be the mean focal distance with which all the light may be conceived to leave the reflector. Describe the circle A E B ; then, because A D B is a parabola, and A E B a circle described about it with the radius C A, and because C A = D F -f- D C, the height D F of the parabola = ^ the height E F of the segment A E B. ButEF = EC + CF = AC + CF, therefore D F = , and D C the minimum focal distance = D F — C F = A C - C F 2 Let A C = r, T — Tl C F = h, then r = maximum focal distance, and — — = minimum focal distance, (2 r X 3' 1416) (r + h)= surface of segment A F B ; and 4 (r2 — h 2) . 7854 = area of AB or GH. Let x — radius of segment m o n : now the surface of the segment A E B is to the surface of the segment mon as r2 to x2, and the area of the end A B is equal to the surface of the segment m o n, therefore (2 r X 3' 1461) (r -j- h) : 4 (r2 — h 2) *7854 : :r2 : x2 or 2 r (r -|- h) x2 — (r2 - - h2) r 2 whence — (^2) r2_ 2 r (r -f h) C;") or x = \/ r ( Vb Y — But r = maximum focal distance and — — minimum focal distance. Therefore x, the mean focal distance, is a mean proportional between the maximum and minimum focal distances. Let therefore A represent the angle subtended by the reflector from the centre of the light, and a — the angle subtended by the light from the reflector at the mean focal distance, then versed sine | A versed sine I a ' will be the amount of illuminating power obtained by the reflector, that of the lamp being 1. This result differs in its numerical value very little from the former, viz. the area of the reflector divided by the area of the light. Thus, for example, let a reflector whose maximum focal distance is twelve inches, and minimum three inches, be iilu- 2 f 2 214 MR. W. H. BARLOW ON DIFFERENT MODES minated with a standard Argand lamp, the diameter of th ejlame of which is one inch, and its altitude If inch. Here the depth of reflector is 9 inches and the area of its 339'28 end 4 (122 — 62) 7854 = 339’28 inches. And by the first rule = 193'8 is the amount of power obtained. By the second rule we have the angle subtended by the reflector equal 240° ; mean focal distance — \/ 12x3 = 6 inches. The angle subtended by the flame of an Argand lamp, which is in the form of a cylinder, will be greater in the vertical direc- tion than in the horizontal ; in order therefore that we may be able to measure the surface of the segment by its versed sine, we will assume that the light is in the form of a sphere whose apparent surface and intensity is equal to that of the lamp, and therefore equal to it in illuminating power. Now the angle subtended by a sphere whose apparent surface is 175 at a distance of 6 inches is 14° 18' vers* 120° therefore by the second rule Tp c-7-oni = 192-9 amount of illu- v ci b* i y minating power obtained. Let us now suppose Drummond’s lime ball to be placed in the focus to find its illuminating effect. Here the section of the ball, the diameter being -fths of an inch, is -110445, and on the first principle 339-28 •110445 = amount of power. and by the second vers. 120° vers. 1° 47' 27" = 3071 amount of power*. And as it is known that the illuminating power of the lime ball when -f-ths of an inch in diameter is equal to 166 Argand lamps, it follows that a reflector of the above dimensions will give a light equal to 3079 X 16-6 = 51112 Argand lamps, or 264 such reflectors illuminated with Argand lamps ; which agrees with Drummond’s observations^. These rules are equally applicable to lenses, the same effect being produced in them by refraction as in the reflectors by reflection, except the difference between the light absorbed and transmitted. It is, however, almost impossible here to determine the mean focal distance very exactly, the lens being built in pieces ; and its form being square increases the diffi- culty; still if we take the mean between the distance of the focal point from the * It may not be seen immediately why these rules do not give precisely the same numerical results, but it will be found that if the angle of divergence be very great, the position of the reflector will at the extreme edge have a considerable obliquity to the line of direction in which it acts and its apparent surface, and con- sequently its illuminating powers will be reduced. The difference, however, is very small when the mean divergence is under 20°. f Phil. Trans. 1830, p. 390. OF ILLUMINATING LIGHT HOUSES. 215 centre and extreme angle of the lens, in the middle of the thickness of the glass, we obtain a tolerably close approximation. Also, the lens being square, and eight of them forming the circle or system of lenses, 2 ) will be the expression for the light intercepted. For example, let it be required to find the increase of illuminating power obtained by the French lens with its lamp, as used by Drummond in his experiments, the lens being 30 inches square, and the lamp having an intensity equal to 4, and illuminating power equal to 10*4 Argand lamps. , Here the surface of the flame will be 4'55 inches ; therefore by the first rule 302 -jTT-r- = 198 increase of power. Again, the mean focal distance being about 39 inches, a sphere whose apparent surface is 4'55 inches will subtend 3° 31'; hence by the second rule 1 sin 22° 30f vers. 1° 45' 30" = 200. These examples being sufficient for the purpose of illustration, we may now state the conclusion which is derived from the above investigation ; namely, that all reflectors and lenses of the same diameter have the same illuminating power when illuminated with the same lamp, and that decreasing the focal distance, and intercepting more rays, does not increase the illuminating power, but simply the divergence, and con- sequently the surface or space over which it acts. On the Comparison of Lenses and Reflectors in reference to their Perfection as Optical Instruments. The results obtained by the above rules, as to the actual increase of illumi- nating power produced by the use of reflectors and lenses, will of course be consi- derably greater than would be found in practice, no account being taken of the absorption, obstruction, or undue dispersion of the light ; still, however, by comparing their computed powers with those obtained by experiment, we shall be enabled to ascertain their merits as optical instruments. The French lens with its lamp was found by experiment to be equal to 9‘1 reflect- ors 21 inches diameter, illuminated with Argand lamps*. Nov/ by computation (the lens being 30 inches square) and the intensity of its lamp 4, give 302 X 4 = 3600 for its illuminating power. And a reflector 21 inches diameter, with a lamp whose intensity is 1, gives 346 il- luminating power. Therefore the illuminating power of the lens ought to be equal to = 10*4 re- flectors. * Philosophical Transactions, 1830, p. 383. 216 MR. W. H. BARLOW ON DIFFERENT MODES But we can hardly expect the lens to be so perfect an instrument as the reflector, not only from the obstruction of light caused by the zones, but from its being com- posed of separate pieces of glass, each of which has its own focus, which foci will coincide more or less according to the accuracy with which the instrument is made ; and it is doubtless from the want of mathematical exactness in the adjustment and curvature of the pieces of which it is composed, that a small surface of light, such as the lime ball, is observed to produce but little effect when placed in its focus, and that the observed divergence of the lens is greater than the computed. Taking the diameter of the lamp at 3 inches, the maximum horizontal divergence would be 5°, whereas in a revolution of 8 minutes the observed duration of the light was 7 seconds, making the observed angle of divergence 5° 15'. In the reflector the duration was 25 seconds, which gives the observed divergence 18° 45', while the computed divergence is 19° 10', the computed in this instrument exceeding the observed. Yet as eight lenses may be applied to one light, as well as some additional appa- ratus which increases their illuminating power, it possesses an advantage in point of economy when applied to a lighthouse ; for with a lamp, consuming the oil of fifteen or sixteen Argand burners, we are enabled to illuminate eight times 5° 15' or 42° of the horizon, the full power of the light being (with the additional appa- ratus) equal to 1Q'4 reflectors 21 inches diameter; while a reflector frame, such as that at Beechy Head, consumes the oil of thirty burners to illuminate three times 3 8° 45' or 56° 15' of the horizon, the full power of the light being equal to ten re- flectors ; whence it appears that the lenses illuminate three fourths of the number of degrees in the horizon which the reflectors do with the consumption of one half of the oil. But although the sum of the angles of maximum divergence of the eight sides of a system of lenses is equal to three fourths of the sum of the angles of maximum di- vergence of the three sides of a reflector frame in the horizontal direction, yet the vertical divergence of the reflectors is far greater than that of the lenses. The following are the maximum horizontal and vertical divergences of the reflector and lens. Max. Hor. Div. Max. Vert. Div. Reflector 18° 45' 31° 54' French lens .... 5 15 30 The computed vertical divergence is less than this, but the observed horizontal divergence being found more than the computed, the 3° above stated would probably he found sufficiently correct in practice. Hence it appears that the advantage gained by the use of lenses over that of re- flectors, is not dependent upon their greater perfection as optical instruments, but from their using the light more economically, by reason of their having less divergence both horizontally and vertically, and illuminating much less space in the horizon. OF ILLUMINATING LIGHT HOUSES. 217 On Divergences. The actual quantity of divergence necessary in any case is a question of consider- able importance. As regards that in the horizontal direction, we have only to consider the practical question of the proportion of light to darkness in a revolution of the light frame. Thus, for example, three faces, each illuminating 16° of the horizon, and re- volving in 8 minutes, would produce the same effect as six faces, each illuminating 8°, and revolving in 16 minutes. The decision will then be made by reference to the divergence in the vertical direction, the value of which will depend upon the situation of the lighthouse ; for if the vertical divergence be too small, a ship might under pe- culiar circumstances be so near the lighthouse as not to catch the light at all, being, in fact, under the lowest rays ; whereas should the situation of the lighthouse be such that a vessel never can approach within two or three miles of it, it is useless to throw away light upon a part where it can never be wanted ; bearing in mind however that the refraction which now and then takes place might, in the event of the divergence being too small, prevent a vessel on the horizon from seeing the light, even were she at a proper distance to be able to discern it in the natural state of the atmosphere : some little excess therefore of the practical above the computed angle is requisite. The following Table shows the vertical divergence required in lighthouses from 100 to 500 feet above the level of the sea, the distance at which the light is first required to be seen being from half to four miles from the lighthouse. Height of Lighthouse in feet. Distance at which the light is first required to be seen. i Mile. I Mile. 2 Miles. 3 Miles. 4 Miles. 100 o • 4 20 o / 2 1.2 0 / 1 7 o / 0 46 0 36 200 8 40 4 22 2 12 1 30 1 10 300 12 58 6 32 3 18 2 14 1 42 400 17 14 8 42 4 22 2 56 2 14 500 20 28 10 50 5 28 3 40 2 46 The axis of the instrument being supposed to be horizontal, the vertical divergence given in the table is twice the angle formed between the horizontal line and a line drawn from the light to the sea at the distance stated at the head of each column. Thus supposing a lighthouse 300 feet above the level of the sea, and that a vessel could not approach within four miles of it, we should only require 1° 42' vertical di- vergence ; but should a light of that height be so situated that a vessel might pass within one mile of it, we should require 6° 32'. Under which latter circumstances it is clear that the French lens having only 3° could not be made use of. Hitherto, however, we have only spoken of the maximum divergences, without con- sidering the minimum ; but this is far too important a part of the subject to be over- looked, as it is only within the range or angle of minimum divergence that we can see the whole light of the reflector. 218 MR. W. H. BARLOW ON DIFFERENT MODES As regards the vertical divergences, if the maximum be sufficient for the situation of the lighthouse, the minimum will in most cases be enough to admit of a vessel ap- proaching so near that some diminution in the power of the light will not be felt ; and for this reason it is unnecessary to enter very minutely into this part of the question ; we shall proceed therefore at once to notice the action of reflectors and lenses in reference to their horizontal divergences. If we examine the effect of a reflector as it revolves on its frame, when seen from a distance of several miles (that is to say at such a distance that lines drawn from either side of the reflector to the eye may be considered as parallel) it will be found that it first begins to give its assistance when the eye is in the line A C, which is the ex- treme of the angle of maximum divergence, or when the angle formed between the line of the axis C E and a line drawn from the eye to the reflector is equal to half the angle subtended by the light in its focus at the minimum focal distance C F, and the reflected light will first appear at C. A As the reflector continues its revolution the eye is brought into the line GH; G H E being the angle formed between a line drawn from the eye to the reflector and the line of its axis, and F H will be the distance at which the light would subtend that angle : now here the reflected light will have extended itself from C along the surface of the reflector to that part where its distance from the focal point is equal to H F. With H F describe the arc I H I, then I C I is the part of the reflector acting at that time, and the area of the circle of which 1 1 is the diameter multiplied into the intensity of the light will be the illuminating power at that time. In the same manner the illuminating power will continue to increase until the angle formed between the axis of the reflector and a line drawn from it to the eye is equal to half the angle subtended by the light in the focus, at the maximum focal distance F M, when it will have attained its full power, at which it will continue until, by the revolution of the reflector, the same angle is formed on the other side of the axis, that is to say, the light will have its full power only during the range of the angle of minimum divergence, when it will begin to diminish; the reflected light receding from the edges of the reflector, and ceasing at the apex C. OF ILLUMINATING LIGHTHOUSES. 219 But in a parabolic reflector the area of the circles A d A„ B b' B„ C d C„ &c. are to each other as A?2, B b'^2, C dV2, &c., or as D d, Db', D d, &c., or as their equals A a, B b, C c. Let D F A, &c. be any variable angle = 6, the corresponding absciss x, and make D F = p one fourth of the parameter. Then (p + x) cos 6 — p — x, whence l — COS i x = p. 1 + cos i And as the angle 6 depends upon the angle formed between the axis of the reflector, and a line drawn from it to the eye, we are enabled to ascertain the ratio in which the illuminating power in- creases and diminishes, when the reflector makes a revolution in a given time. The following Table shows the illuminating power of the re- flector and lens at the end of every second of time during the passage of the light. The reflectors with Argand lamps being supposed to be placed on three sides, and revolving in 8 minutes, that with the lime ball and the lens having eight sides, and revolving in 21 minutes 20 seconds, making the time from the appearance to the re- appearance of the light in each 160 seconds. The illuminating powers are expressed in Argand lamps as placed in reflectors 21 inches diameter. Seconds of Time. 3 Sides. 3 Sides. 8 Sides. 8 Sides. I Single Reflector with Argand Lamp. Ten Reflectors with Argand Lamp. Single Reflector with Lime Ball. French Lens. 1 •0285 •285 7-72 ? 2 •0617 •617 16-51 ? 3 •1019 1-019 27-33 10-4 4 •1501 1-501 40-66 10-4 5 •2133 2-133 57-48 10-4 6 •2937 2-937 79-35 10-4 7 •4019 4-019 108-98 10-4 8 •5555 5-555 151-35 10-4 9 •7905 7-905 216-98 10-4 10 1-0000 10-000 264-00 10-4 11 1-0000 10-000 264-00 10-4 12 1-0000 10-000 264-00 10-4 13 1-0000 10-000 264-00 10-4 14 1-0000 10-000 264-00 10-4 15 1-0000 10-000 264-00 10-4 16 1-0000 10-000 264-00 10-4 17 •7905 7-905 216-98 10-4 18 •5555 5-555 151-35 j 19 •4019 4-019 108-98 ? 20 •2937 2-937 79-35 Dark. 21 •2133 2-133 57-48 22 •1501 1-501 40-66 — 23 •1019 1-019 27-33 24 •0617 •617 16-51 25 •0285 •285 7-72 — 26 Dark. Dark. Dark. 2 G MDCCCXXXVII. 220 MR. W. II. BARLOW ON DIFFERENT MODES From the above Table it will be seen, that taking the fall power of a reflector in connection with the duration due to its maximum divergence, gives a very inadequate idea of the quality of the instrument ; and that from the high ratios in which the illuminating power increases and diminishes immediately before and after the brightest period, the duration due to the minimum divergence is all we can depend on, if the distance and state of the weather be such as to require the full power of the instrument ; and as it is under circumstances like these that our beacon lights are most called for to give their aid to the benighted mariner, the duration of the brightest period becomes one of the most essential qualities to be attended to. In comparing the lenses with the reflectors in this respect, we find (by referring to the above Table) that when the revolution is made so that the time from the ap- pearance to the re-appearance of the light is equal in each, the duration of the brightest period is as 14 to 6, that is to say, the number of degrees of the horizon illuminated with the brightest light by the eight sides of a system of lenses, is to the number illuminated with the brightest light by the three sides of a reflector frame as 14 is to 6. Consequently we should require seven sides to our reflector frame to be equal in this respect to the lenses ; and as each side must have ten reflectors to be equal in power to the lens with its additional apparatus, we should require to con- sume the oil of seventy Arganb lamps to produce the same effect with the present construction of our reflectors, as that which is obtained in the lenses with the con- sumption of fifteen or sixteen Argand lamps. Before, however, we give an opinion as to whether the lens or the reflectors is the best instrument for our lighthouses, or before we examine whether any improvement can be made in them, we must first consider the situation and purposes of the light- houses to which they are to be applied. On the Situations and Purposes of Lighthouses , and the Application of Lenses and Re- flectors to the Duties required in them. Lighthouses may be divided into three classes, viz. First. Beacon or warning lights, being those which are placed to warn a vessel, and to which she can never be nearer than three or four miles. Secondly. Guiding or leading lights, being those which are placed to guide a vessel, and to which she may approach very closely. Thirdly. Lights which have both these duties to perform, being those which are placed to warn a vessel from a danger at a considerable distance in one direction, while they may be approached with safety in another. In the first we require great illuminating power and a long duration of the brightest period, with a small angle of vertical divergence. In the second less illuminating power is required, but a large angle of vertical divergence, the duration of the ex- treme brightness not being of so much importance. In the third we require great OF ILLUMINATING LIGHTHOUSES. 221 illuminating power, a long duration of the brightest period, and a large angle of ver- tical divergence. The comparative qualities of the French system of lenses, and a first class light with reflectors, such as that at Beechy Head, as to their application to the above duties, will be seen in the following statement. Oil consumed in 3| hours .......... Illuminating power without the instruments expressed in Argand lamps Illuminating power with the instruments expressed in reflectors with Argand lamps ........ Maximum horizontal divergence per side . . . . . Minimum horizontal divergence per side . . . . . Number of sides ............. Degrees of horizon illuminated ........ Degrees of horizon with the full power ...... Maximum vertical divergence ......... First Class light with ten Reflectors on a side 21 in. diameter. 4 qts. Ipt. French Lens with its additional ap- paratus. 2 qts. | pt 30 10-4 10 10-4 18° 45' 5° 15' 4° 46' 4° 4' 3 8 56° 15' 42° 0' * O 00 32° 32' 31° 54' 3° 0' From the above it will be seen that for a beacon light, when not more than 3° of vertical divergence is required, the lens is far the cheapest and best instrument, on account of its greater power and longer duration of the brightest period, although the illuminating power without the instrument is obtained at a greater consumption of oil than in the Argand burners ; and that the reflectors as at present constructed are best adapted for leading or guiding lights, where a very large angle of vertical divergence is required. But in all those situations where more than 3° of vertical divergence are wanted, the lens is inapplicable, and where less than 30° are required there would be a useless waste of light in the reflectors. Now this is undoubtedly by far the most numerous class of lighthouses, we shall therefore examine with what advantage an alteration may be effected in the vertical divergences of the above in- struments ; but as many circumstances, such as the accuracy with which the instru- ment is made and fixed, atmospheric refraction, and a little variation in the height of the flame of the lamp would all tend to render variable the range of the angle of ver- tical divergence, we shall not attempt to employ very great exactness in this respect. Considering these circumstances, the natural vertical divergence of the lens is the least that ought to be employed in any situation ; and as the height of the flame which oil is capable of supporting to burn with advantage is nearly the same whatever may be the dimension of the lamp, the only way in which this divergence can be increased is by shortening the focal distance, to do which we must either reduce the area of each lens or the number of sides ; the one would produce a loss of illuminating power, and in the others the figure of the instrument would become more distorted, and the greater obliquity with which the rays would strike and leave the lens would also be a cause of loss of light. Gas might perhaps be applied here with advantage, for by 2 g 2 222 MR. W. H. BARLOW ON DIFFERENT MODES having five or six concentric burners the same intensity of light might be obtained, while the greater height of the flame would give a greater vertical diverging angle. But in the reflector where the vertical divergence admits of so much reduction, we are enabled to increase the focal distance, and consequently to employ a large reflector, by which means a considerable saving would be effected in the consump- tion of oil, or using the same oil, we might obtain a much greater illuminating power. If, for example, we employed a reflector 42 inches diameter, with six inches focal di- stance, the illuminating power depending on the area of the end would be equal to four of the usual reflectors, but the divergences would all be reduced one half, we should consequently require six sides instead of three to illuminate the same number of degrees in the horizon, so that by reducing the vertical divergence to 15° we obtain the same illuminating power with half the consumption of oil. Instead, however, of employing twice as many reflectors to produce the same durations, we might double the diameters of the lamps and use the same number as at present. Before proceeding further with this part of the subject, it will be necessary to say a few words regarding the consumption of oil to produce a given illuminating power in lamps of different sizes and constructions. In the French lamp the consumption of oil to produce the same illuminating power as the Argand burners is nearly as 1|- to I, but here there are four concentric wicks, the largest of which is not more than three inches in diameter, and there would in consequence be a great intensity of heat, which would cause a considerable portion of the oil to pass off in vapour ; but by increasing the diameter of a single wick, the intensity of heat would not be increased, we may therefore consider that the consumption would be exactly as the illuminating power. I am not aware of any experiments having been made to ascer- tain the consumption in lamps of two and three wicks, and it would perhaps be found to vary a little with their dimensions, but as we find the illuminating power to be obtained at 1 to 1 in the Argand lamp which has one wick, and as 1^ to 1 in the French lamp which has four, it will be sufficiently near for our purpose to assume that the consumption of oil to produce a given illuminating power will be as follows: In a lamp with one wick as 1 to 1. In a lamp with two concentric wicks as to 1. In a lamp with three concentric wicks as 1^ to 1. In a lamp with four concentric wicks as 1^ to 1. And as we find that a lamp with one wick has an intensity of 1, and that the French lamp which has four wicks has an intensity of 4, it appears that the intensity in- creases directly as the number of wicks. Calculating then as above, we should evidently obtain the illuminating power of ten reflectors at the cheapest rate, by employing a reflector the area of whose end should be equal to ten, with a lamp having only one wick ; but as this would lead to such unwieldy instruments, it would doubtless be preferable to diminish the size of the apparatus by increasing the intensity of the lamps, and if it be within practicable OF ILLUMINATING LIGHTHOUSES. 223 limits to make reflectors four feet in diameter, and seven inches focal distance, we might by employing three such reflectors with lamps 2\ inches in diameter, having two concentric wicks, produce the same illuminating power and the same durations as the Beechy Head lighthouse, the vertical divergence being 14°, and the consump- tion equal to about seventeen or eighteen Argand burners. Still, however, there would be only 14° 14' of the horizon illuminated with the brightest light, but an improvement may be made in this respect by altering the form of the reflector, for as all reflectors of the same diameter have the same illumi- nating power when illuminated with the same lamp, that which has the greatest angle of minimum divergence, or the longest duration of the bright period, will be that in which the distance A F is the shortest, that is to say when the focus is in the plane of the end of the reflector, and it is not improbable that having by this means less reflect- ing surface there would be less absorption and a better light. />But in increasing the duration of the brightest period we diminish the angles of maximum divergence both horizontally and vertically. The divergences of a reflector four feet diameter and 7 inches focal distance with a lamp 2\ inches diameter would be. Vert. Div. 15° 22' Max. Hor. Div. 18° 34' Min. Hor. Dii 4° 42' whereas if the focus were in the plane of its end they would be Vert. Div. Max. Hor. Div. Min. Hor. Div. 8° 22' 4 10° 46' 5° 22' But notwithstanding the great reduction in the angles of maximum divergence, I have no hesitation in considering this to be the best form of reflector when the vertical divergence required by the situation of the lighthouse will admit of its ap- plication, as it gives the longest duration to the bright period ; for if the distance and state of the weather be such that it becomes a question whether the light be seen or not, the spread of weaker light will of course be invisible, and if the light be seen distinctly this weak light is not required, the regular appearance and disappearance of the light at known intervals being all that is necessary ; such light, however, ought not to be used for purposes of distinction, as its duration is subject to great variations from distance or the state of the weather. What number of degrees in the horizon it is necessary to illuminate, and more par- ticularly what number it is necessary to illuminate with the brightest light, is a ques- tion upon which no determination appears to have been arrived at, but there can be no doubt in applying a given illuminating power (say that of ten reflectors 21 inches diameter,) to a lighthouse, that having attained a sufficient vertical divergence for its situation, the rest of the light cannot be better employed than in increasing as 224 MR. W. H. BARLOW ON DIFFERENT MODES much as possible the length of the period during which the full power of the instru- ment is acting, or the number of degrees in the horizon illuminated with the full power of the instrument, however much the spread of weaker light may be dimi- nished by so doing. From the foregoing it would, appear that the best mode of applying lenses and re- flectors to lighthouses when illuminated with oil is as follows. When less than 3° of vertical divergence is required. The French lens is to be preferred with its additional apparatus by which 32° 82f of the horizon is illuminated with a light equal to 10‘4 reflectors 21 inches diameter, the sum of the angles of maximum horizontal divergence being 42° O', and the con- sumption of oil equal to fifteen or sixteen Argand burners. For more than 3° and less than 8° vertical divergence. Reflectors four feet diameter should be employed, if practicable, with the focus in the plane of the end. Four such reflectors with lamps 2- inches diameter having two concentric wicks would illuminate 21° 28' of the horizon, with a light equal in power to 10*4 reflectors 21 inches diameter, the sum of the angles of maximum hori- zontal divergence being 43° 4', and the probable consumption equal to twenty-three Argand burners. Or three such reflectors with lamps 2\ inches diameter having three concentric wicks would illuminate 17° 54' of the horizon, with a light equal in power to fifteen reflectors 21 inches diameter, the sum of the angles of maximum horizontal diver- gence being 35° 54', and the probable consumption equal to thirty Argand burners. For more than 8° and less than 15° vertical divergence. Reflectors four feet in diameter may be employed with the focal distance so ar- ranged as to give the vertical divergence required. And for more than 15° vertical divergence it will perhaps be found better to use smaller reflectors and more in number. This last, however, is a case which will rarely occur in lights where great illuminating power is required. It is proper, however, to observe generally, that the lens is liable to one practical objection, viz. that depending on one light only, any accident whereby it becomes ex- tinguished leads to total darkness, which is not so likely to happen in a system of reflectors which has several lights to depend on. OF ILLUMINATING LIGHTHOUSES. 225 P.S. Since writing the above, it has occurred to me that a considerable increase of illuminating power would be obtained in a reflector whose focus was in the plane of its end by the application of a spherical reflector (as in the annexed figure) to in- tercept the rays which would otherwise be lost, and thus to return them through the light itself, and thereby increase its intensity. The spherical reflector ought to be made about one fifth of the diameter of the parabolic reflector, and a little less than a semisphere, so as just to be without the lines A C. Here it will be seen that the light upon the part d d will be doubled through all its divergences, minus the absorp- tion of light in the spherical reflector, and the area of light obstructed by it. If the spherical reflector were made of glass silvered (in which I find from experiment, that the absorption of light is about two fifths,) the increase of illu- minating power obtained by this means in the parabolic re- flector would be about one third or one fourth. The effect of a coloured light might also probably be pro- duced by a similar segment of coloured glass between the lamp and reflector. [ 227 T J XIV. Researches on the Tides. — Eighth Series. On the Progress of the Diurnal In- equality Wave along the Coasts of Europe. By the Rev. W. Whewell, M.A.F.R.S. , Fellow of Trinity College, Cambridge. Received June 14, — Read June 15, 1837. In the Seventh Series of these Researches I have pointed out the laws which the diurnal inequality of the height of high water follows, and which I believe had never before been collected from the facts of observation, or indeed stated at all. I have also shown that these laws are modified so as to exhibit very remarkable differences at different places, and to give rise to some difficulty in conceiving the mechanical propagation of the tide-wave. I suggested what appeared to me a possible solution of the difficulty ; but as this suggestion was founded upon the facts of a few places, and as other modes of propagation might perhaps also be conceived and adapted to the same facts, the subject remained incomplete. I resolved therefore to attempt to trace the progress of the wave which brings the diurnal inequality, on some of the coasts on which simultaneous observations were made at my request in June 1835, and the present memoir will give some account of the conclusions to which I have been led by this investigation. The diurnal inequality of the height of high and low water may be conceived to arise from an oscillating wave, of which the maximum height comes to each place once in twenty-four (lunar) hours ; the minimum height arriving, of course, at the intermediate twelve hours. If the time of the maximum height of this wave arriving at any port coincides every day with the time of high water, the alternate high water, being at twelve hours’ interval, will be affected alternately with the greatest and least heights of the diurnal wave ; and the intermediate low waters will coincide with the mean height of this wave, and will not be affected at all. In this case there will be a decided diurnal inequality in the height of the high water, but no diurnal inequality in the height of low water. In like manner if the time of the maximum height of the diurnal wave coincide with the time of low water, the height of low water will be marked with a diurnal inequality, while the height of high water will exhibit no such feature. But if the diurnal wave arrive every day at a time intermediate between high and low water, it will elevate both the high water and the low water which are nearest to it, and will depress both the high and the low water which happen in the other half of the day. Hence both the high waters taken separately, and the low waters taken separately will be marked by a diurnal inequality ; and this inequality MDCCCXXXVII. 2 H 228 THE REV. W. WHEWELL ON THE PROGRESS OF THE will be greater for high water or for low water, according as the time of the maximum of the diurnal wave is nearer to the time of high or of low water. Hence by taking the diurnal inequality of high and of low water at any place, and by combining these effects, we may determine the time of the arrival of the diurnal portion of the tide, and also its magnitude ; and may thus separate this tide wave from the semidiurnal wave which brings every tide. And the time and magnitude of the diurnal wave being thus determined at a series of places along any coast, we trace its progress nearly in the same manner as we do that of the tide itself. This is what I have done in the Tables subjoined at the end of this memoir. The heights of high water, for example, observed in June 1835 (from the 9th to the 28th) were laid down as ordinates, and a line was drawn connecting them. This line, when the diurnal inequality was manifest, was a zigzag line, such as is represented for Plymouth and for Singapore, in the figures to the Seventh Series of these Researches, and for several places in America and Europe in the Sixth Series. The line of mean heights was then drawn, cutting off all the diurnal inequalities. The same was done for low water; and the diurnal inequalities of the high and low waters, thus cut off, were tabulated in order. In general they were, of course, alternately two additive and two subtractive sums. These sums were laid down as ordinates at certain in- tervals, which intervals represent half tides (six lunar hours) ; and the curve drawn through the extremities of these ordinates is the diurnal wave according to its changes from day to day at the same place. The assemblage of the circumstances of such waves at different places gives the progress of the wave along the coast. The forms of the curves thus representing the diurnal wave being determined for a sufficient number of places, it is easy to see what relations among these forms would indicate the different modes of propagation of the diurnal inequality which may be supposed. In all cases this inequality, depending as it does upon the moon’s decli- nation north and south, would increase from nothing to a maximum, and decrease to nothing again in about a fortnight ; after which the inequality becomes negative, increases to a negative maximum, and decreases to nothing again in another fort- night, and so on. The epochs at which the inequality vanishes correspond to the times when the moon crosses the equator, but occur after those times at intervals varying from a few hours to four or five days, and perhaps more. It appeared to ine, from the cases which I considered in my last memoir, that the epoch gradually in- creases as we proceed along the coast in the direction of the progress of the semi- diurnal tide wave ; and that this increase of epoch goes on much more rapidly than the increase of epoch for the inequalities due to the moon’s parallax and declination; so that the diurnal inequality is propagated much more slowly than the other in- equalities, and employs, for example, two days or more to make its way from the coasts of Spain to those of England ; or, as I have before expressed it, the diurnal in- equality creeps along the coast from day to day. Another mode in which we might explain different modifications of the diurnal inequality which the observations at DIURNAL INEQUALITY WAVE ALONG THE COASTS OF EUROPE. 229 different places exhibit is this : we may suppose that the diurnal wave has the same epoch as me semidiurnal wave., but that the former wave travels with a different velocity from the latter. The consequence of this would be that the diurnal inequality would at one port be thrown entirely upon the high water, at a place at some distance, where the diurnal wave had gained (or lost) six (lunar) hours upon the semidiurnal wave, the diurnal inequality would fall entirely upon the low water, and would not appear in the high water at all ; and at intermediate places it would affect both high and low waters. If neither of these cases appear to agree with the facts, there ap- pears to be no supposition remaining but that the diurnal wave travels irregularly, so as to affect only or principally sometimes high water, sometimes low water, some- times both, with no regular progression. And in this case it may be conceived that the diurnal wave at some places vanishes or becomes very small, as I have shown in the Sixth Series of these Researches that the semidiurnal wave does, even in the near neighbourhood of places where it is of considerable magnitude. The form of the curve which represents the diurnal wave at a series of ports would be modified in the following manner on these different suppositions. If the epoch of this wave changes more rapidly than that of the other inequalities, the sinuous curve which represents the diurnal wave, will have its zero ordinates, and its maximum or- dinates, gradually transferred from one half day to a succeeding one, and so on, as we proceed in the direction of its propagation. Each of the sinuous swells , corre- sponding to the successive tides, may remain in the same place, but the assemblage of them, corresponding to a semimenstrual series of north or of south lunar declina- tions, will glide forwards by an alteration of the values of the maximum ordinates in these diurnal swells. On the other hand, if the epoch were the same at different places, and the velocity of the diurnal wave different from that of the semidiurnal wave, each diurnal swell will slide on, separating itself more and more from the cor- responding high (or low) water, but undergoing no progressive change in its mag- nitude. The form of the diurnal wave curve was thus determined for several series of places, and I will state the conclusions to which these series respectively led*. First Series. — Ferrol, Port Magee (west end of Valentia Island), Doonkeghan (Mayo), Sligo, Ballynass (in the north-west of Ireland), Scrabsters (near Thurso), Buckie, Uzon (near Montrose), North Berwick (Frith of Forth), Berwick-upon-Tweed, and Clay Hole (Lincolnshire). This series begins on the west coast of Spain, and proceeding by the west coast of Ireland to the north of Scotland, turns round the north-east point of Scotland, and goes on along the east coast of Britain. It appears, in the first place, by the inspection of these curves, that there is no such slow propagation of the diurnal inequality as I had supposed. The inequality vanishes at all these places about the 10th and 22nd of June, the moon’s declination having * The curves for a series of places on the coasts of the British Channel are given in Plate XIV. 2 h 2 230 THE REV. W. WHEWELL ON THE PROGRESS OF THE vanished on the 6th and on the 18th. Thus the epoch is the same, or nearly the same, at all these places, namely, about four days, which is the value I had already assigned to it from several years’ observations at Plymouth. It appears to be half a day, or perhaps a day greater than this on the east coast of Britain, but on that coast the tide has been from half a day to a day longer in arriving ; so that we have here nothing to favour the opinion that the diurnal inequality is transferred at a different rate from the other inequalities of the tides, and the suggestions contained in my last memoir respecting the laws and causes of the supposed peculiar movement of the diurnal inequality must be rejected. They were founded principally on observations made at Leith, in which the diurnal inequality was very imperfectly exhibited ; the rejection of them is founded on observations made at sixty-five places, taken in order along the coasts of England, Ireland, and Scotland ; for I have examined the diurnal inequality at many places on those coasts, besides those for which I have drawn the curves of the first series, and I find a general agreement in the features of contiguous places. The slow propagation of the diurnal inequality from day to day being thus rejected, we have next to consider the motion of the diurnal wave for each day, by means of our curves. It will be observed that in each curve the alternate strong ordinate lines belong to high waters, and the intermediate lines to low waters. The maxima of the swells of the curves, above and below the axis, are the summits of elevation and de- pression of the diurnal wave, and by the position of these summits with regard to high and low water, we see whether the diurnal wave arrives before or after the semi- diurnal wave, and by how much. And as we know at each place how long the semi- diurnal wave arrives after the moon’s transit, we thus can refer the diurnal wave to the moon’s transit. In doing this we must make a distinction between the superior and inferior transit, which does not affect the semidiurnal waves. The diurnal wave belonging to the superior transit will (by theory) increase the tide when the moon’s declination is north, and diminish the tide when the declination is south. Hence if we consider our diurnal wave as belonging to the moon’s superior transit, since from June 6th to June 18th, 1835, the moon’s declination is south, we must take the lower summits of the curve from June 10th to June 22nd ; and the mode of proceeding is obvious. At Ferrol, for example, it will be seen that the lower summits of the diurnal wave occur in general about two hours before the high water ; and this is the high water which follows a superior transit; for on June 16th, for instance, it is the morning tide which occurs at 6h 42m, the moon’s transit occurring June 16th 4h 53m a.m. Now the tide at Ferrol, taking the average interval (the “corrected establishment” of my former Researches), follows the moon’s transit at an interval of 2 hours and thirty minutes. Therefore the diurnal wave at Ferrol follows the moon’s superior transit at an interval of thirty minutes. The following is the result of the investigation in this series of places. DIURNAL INEQUALITY WAVE ALONG THE COASTS OF EUROPE. 231 Comparing the diurnal wave, which brings the diurnal inequality of high and of low water, with the semidiurnal wave, which brings every tide, we find that At Ferrol, the diurnal wave is about 2§ hours earlier. At Port Magee, about 4 hours earlier. At Doonkeghan, about 2 hours earlier. At Sligo, about 1| hour earlier. At Ballynass, about 1 hour later. At Scrabsters, about 4 hours earlier. At Buckie, about 4 hours earlier. At Uzon, about 5 hours earlier. At North Berwick, about 3 hours earlier. At Berwick-upon-Tweed, about 4 hours earlier. At Clay Hole, about 2 hours earlier. These quantities are unavoidably somewhat vague ; for the place of the summit of the wave, as determined by four points of the curve, is necessarily liable to uncer- tainty, arising from its form not being known ; besides which it is affected by acci- dental causes. And it may be seen by the diagrams that the distance of the summit from high or low water often differs considerably on different days. The curve at Ballynass, where the diurnal wave differs most from the general average, is very irregular. The above quantities, therefore, do not afford us any clear evidence of a progressive separation of the diurnal from the semidiurnal wave. And the varia- tions which lake place in the diurnal inequality at different places, may be referred to a partial acceleration or retardation of the diurnal wave. Thus on the east coast of Scotland (at Uzon, near Montrose), the diurnal wave shoots on before the semi- diurnal, so as to arrive five hours sooner than that ; consequently it nearly coincides with low water, and the diurnal inequality of low water is great, while that of high water almost vanishes. But at North Berwick, in the Frith of Forth, this displace- ment of the diurnal wave is almost corrected, the diurnal inequality affecting high and low waters almost equally. We appear to be led by this course of investigations to the conclusion, that the differences of diurnal inequality at different places are governed by local circum- stances, and do not form a progressive series. We need the less be surprised at this, having already seen (in the Sixth Series of these Researches,) that the amount of the rise of the tide differs very much even within small distances along the coast, or across the sea, and follows no progressive course of increase or decrease. And we may hence explain the cases, many of which occur, in which places having no diurnal inequality are interposed in a line of coast along which the inequality prevails : for example, at Baltimore, near the south-west point of Ireland, the diurnal inequality is not perceptible, either at high or low water, in the observations of June 1835, (which were carefully made,) although it is very conspicuous both on the west and on the south coast of the island. 232 THE REV. W. WHEWELL ON THE PROGRESS OF THE Second Series. — I now proceed to consider another series of places taken on the coasts of the British Channel, namely, Ferrol, Brest, Cherbourg, Havre, on the con- tinental coast, and Penzance, Plymouth, Bridport, Lulworth and Portsmouth on our own shores. As before, comparing the diurnal with the semidiurnal wave, we find that At Ferrol, the diurnal wave is 2f hours earlier. At Brest, 3|- hours earlier. At Penzance, 2% hours earlier. At Plymouth, 2\ hours earlier. At Cherbourg, 4 hours earlier. At Havre, 3 hours earlier. So far the two waves appear to go on nearly with the same velocity ; but the Isle of Wight appears to produce a disturbance. For proceeding onwards, we find that At Bridport, the diurnal wave coincides with the semidiurnal. At Lulworth, the diurnal wave is five hours later. At Portsmouth, it is 4^ hours later. It appears, therefore, that at this point, where St. Alban’s Head and the Isle of Wight interpose themselves in its course, the diurnal wave receives a check which almost reverses its position, and makes the inequalities very different at places be- fore and after that point. Nor does this assertion rest upon any arbitrary mode of combining the facts, but it appears in the facts themselves. For instance, if we com- pare the high waters at Plymouth, and at Lepe, near Southampton, we shall find that their relation is contrary, the morning high waters being lower than the mean, and the evening high waters higher than the mean, from June 14 to 18 at Plymouth, and the same being the case at Lepe ; although the morning tide of one place is identical with the evening tide of the other. We may observe, that we have here a new proof of that, of which the recent ex- amination of the tides has supplied many proofs, that we can by no means reason on the supposition that the waters of the ocean approximate to a level surface, or that an elevation at one place is necessarily shared by the surrounding seas. We may also observe, that the part of the Channel where the diurnal wave is thus held back, had already been found to be marked by peculiar tidal features ; the cotidal lines turning round the promontories above mentioned as a kind of hinges, in con- sequence of the slow progress of the tide-wave near the shore. It is probable that the peculiarities which we thus discover to coexist in the motion of the diurnal and of the semidiurnal wave would be found to be connected, if we could analyse the hydrodynamical laws of the ocean. The motion of the diurnal wave being thus irregular, we can account for the variety of values of the diurnal inequality at different places. We can also conceive this wave to move in a manner even more irregular than we have yet described ; and DIURNAL INEQUALITY WAVE ALONG THE COASTS OF EUROPE. 233 some of the facts do appear to indicate this farther irregularity. For example, the diurnal inequality appears sometimes, for several days, to leap from its proper tides to the alternate tides, without vanishing* in the transition, as in rule it does. Now this irregular movement may be accounted for by supposing- that the diurnal wave, which usually completes its oscillation and returns in twenty-four (lunar) hours, does sometimes occupy a longer or shorter time in the oscillation. If, for instance, this wave, after arriving four hours before the superior high water of one day, arrive again twenty hours afterwards and therefore eight hours before the superior tide of the next day, it will be only four hours after the inferior high water of the second day; and therefore the diurnal inequality will pass from the superior to the inferior tide by a leap. There appear to be several cases implying a change of this kind, but the subject is so complex and so laborious that I shall not now pursue it. I venture to observe, that what has been recently done in the prosecution of our knowledge of the tides, proves the claims which it has for the same kind of attention and support which is given to other branches of astronomy. The immense labour of following out any one portion of this subject may be judged of, from a very slight attention to any part of the researches of Mr. Lubbock and myself upon it. In the present memoir I have selected the best-conditioned and most carefully made obser- vations out of the general mass of those made in June 1835. I have had the curves of high and low water drawn for seventy-one such places. From among these, I have taken the nineteen places mentioned in this memoir, and have caused the diurnal wave curves to be tabulated and drawn, of which a series is represented in the diagram. These calculations and diagrams have been performed by Mr. D. Ross of the Ad- miralty, without whose services, placed at my disposal by the First Lord of the Ad- miralty, it would have been impossible for me to proceed. And even with all the assistance which can thus be given, the superintendence of the subject of the tides alone might fully employ one man of science, with great advantage to the progress of our knowledge ; the subject being now so far opened that it is pretty clear in what manner research may be profitably pursued. There is another reason why tide investigations should be made a national work in civilised maritime states. The peculiarities of the tides in each country are such as to make each shore a study by itself, and our best generalizations will be collected from results obtained in separate parts and combined. I have given less of my labour to the coasts of the United States of North America than might have been due to the interest of the tides of that part of the Atlantic, because I was obliged to limit my labour in some direction, and I hoped, and do hope, that the subject will be taken up by the government of that country as well as our own. Suffolk Street , June 15, 1837- 234 THE REV. W. WHEWELL ON THE PROGRESS OF THE List of Places examined for Spain. Ferrol. Coast of France. Brest. St. Servan. Cherbourg. Havre. D’Ouessant. Scotland toward Thames. 4 a * Scrabsters. 6 a Buckie. 6 a! Cullen. 6 e Fraserburgh, 7 e Cove Bay. 8 c Uzon. 10 a North Berwick. 11a Berwick-upon-Tweed, 14 h Clay Hole. 18/ Kessingland. Thames to Land’s End. 259 Kingsdown. 26 e No. 3 Tower, near Dovor. 26 k Fort Sutherland. 29 l Chichester Harbour. 30 l Langstone Harbour. 30 d Portsmouth. 30 g Hamble River. 31a Cowes Harbour. 316 Ryde. 31 d Sandown. 3 1 g Freshwater. 31 ‘i Newtown. 32 b Lepe. 32 g Christchurch. 34 a Lulworth. 34 c Weymouth. * These numbers and letters refer to the Coast ( searches. Progress of the Diurnal Wave. 35 c Bridport Harbour. 35 e Lyme Cobb. 36 a ' Weston. 36 d Dawlish. 37 d Tor cross. 37/ Salcombe. 37 h Challabro. 38 c Bovisand. Plymouth. 38 /Port Winkle. 39 c Polruan. 40 d Coverack. 416 Penzance. Coast of Ireland. 49 Arthurstown. 53 e Baltimore. 54 White Horse Station. 55 6 Ballinskelligs. 55 c Port Magee. 56 6 Dingle. 57 a Castle Gregory. 58 a Kilrush. 59 c Bally onughan. 59^r Littermore. 61 c Innisbuffin. 62 Elly Bay. 63 a Doonkeghan. 63 6 Port Tulin. 63 /Kilcummin. 64 dd Sligo. 65 6 Trybane. 65 e Port Nov. 66 Guidore. 66 c Port Ballynass. 68 / Torr Head. 70 /Ballywater. 71c St. John’s Point. 72 c Dunany Point. 73 cBalbriggan. 73 mHowth. , Stations as arranged in the Sixth Series of these Re- DIURNAL INEQUALITY WAVE ALONG THE COASTS OF EUROPE. 235 Tables of the Effect of the Diurnal Inequality on Low and High Water in June 1837- [From these Tables curves were constructed, by means of which the conclusions contained in the preceding memoir respecting the diurnal wave were established.] Ferrol. Ferrol. Ferrol. Tide. Time. Diurnal Inequal. Tide. Time. Diurnal Inequal. Tide. Time. Diurnal Inequal. 1835. h m 1835. h m 1835. h m June 9 a.m. H. 53 0 June 16 a.m. L. 35 — 5 June 23 a.m. H. 56 - 1 L. 6 57 — 2 H. 6 49 — 7 L. 7 17 — 1 P.M. H. 1 19 0 P.M. L. 42 + 5 P.M. H. l 13 + 2 L. 7 29 + 2 H. 7 17 + 10 L. 7 17 + 2 10 A.M. H. l 40 + 3 17 a.m. L. l 22 — 1 24 A.M. H. l 40 - 4 L. 7 50 — 1 H. 7 43 — 7 L. 7 33 — 1 P.M. H. 2 7 0 P.M. L. 1 52 — 5 p.m! H. 1 50 + 2 L. 8 12 — 2 H. 8 15 + 8 L. 7 50 -|- 1 11 A.M. H. 2 33 — 3 18 A.M. L. 2 22 — 1 25 A.M. H. 2 13 — i L. 8 38 + 1 H. 8 50 — 6 L. 8 18 0 P.M. H. 2 48 + 3 P.M. L. 3 2 + 3 P.M. H. 2 29 + 2 L. 9 12 — 2 H. 9 8 + 6 L. 8 42 0 12 A.M. H. 3 28 — 4 19 a.m. L. 3 37 — 2 26 A.M. H. 2 49 - 5 L. 9 26 + 4 H. 10 7 — 5 L. 8 40 0 P.M. H. 3 47 + 5 P.M. L. 3 50 + 3 P.M. H. 3 4 + 5 L. 9 56 — 5 H. 10 23 + 4 L. 9 10 0 13 A.M. H. 4 ii — 5 20 A.M. L. 4 33 12 27 a.m. H. 3 30 — 3 L. 10 10 + 4 H. 11 6 — 3 L. 9 9 0 P.M. H. 4 17 + 7 P.M. L. 5 1 + 1 P.M. H. 3 46 + 5 L. 10 56 — 5 H. 11 16 + 3 L. 9 24 — 1 14 A.M. H. 5 3 — 6 21 A.M. L. 5 30 — 2 28 A.M. H. 4 14 - 6 L. 10 58 + 4 H. 11 58 — 1 L. 9 49 + 1 P.M. H. 5 19 + 7 P.M. L. 5 52 + 1 P.M. H. 4 14 + 8 L. 11 42 — 5 22 A.M. H. 1 — 1 L. 10 30 — 1 j 35 A.M. H. 5 58 — 7 L. 6 5 — 1 L. 11 52 + 4 P.M. H. 32 + 1 P.M. H. 6 19 + 9 L. 6 32 + 1 Brest. - Brest. Brest. June 9 a.m. H. 1 49 1 June 16 a.m. L. 1 40 7 June 23 a.m. H. 1 49 + 2 L. 8 10 + 1 H. 7 45 — 5 L. 8 2 0 P.M. H. 2 17 + 1 P.M. L. 2 5 + 4 P.M. H. 2 7 0 L. 8 38 — 1 H. 8 9 + 6 L. 8 24 2 10 A.M. H. 2 44 — 1 17 a.m. L. 2 31 — 3 24 A.M. H. 2 27 0 L. 9 2 + 1 H. 8 36 — 4 L. 8 45 + 6 P.M. H. 3 15 0 P.M. L. 3 1 + 3 P.M. H. 2 50 + 6 L. 9 30 — 1 H. 9 6 + 7 L. 9 7 0 11 A.M. H. 3 38 -r 1 18 A.M. L. 3 29 — 2 25 A.M. H. 3 7 — 1 L. 9 57 + 2 H. 9 31 — 4 L. 9 22 0 P.M. H. 3 59 + 4 P.M. L. 3 53 + 2 P.M. H. 3 24 + 1 L. 10 19 — 3 H. 10 4 + 5 L. 9 40 - 2 1 2 A.M. H. 4 25 — 2 19 a.m. L. 4 32 — 3 26 A.M. H. 3 42 — 3 L. 10 45 + 3 H. 10 36 — 3 L. 10 1 + 1 P.M. H. 4 51 + 4 P.M. L. 5 0 + 1 P.M. H. 4 4 + 10 L. 11 9 — 4 H. 11 8 + 3 L. 10 23 0 13 A.M. H. 5 12 — 4- 20 A.M. L. 5 36 — 1 27 A.M. H. 4 25 2 L. 11 33 + 5 H. 11 40 — 2 L. 10 40 0 P.M. H. 5 38 + 5 P.M. L. 6 4 + 2 P.M. H. 4 37 + 2 L. 11 58 — 4 21 A.M. H. 2 + 3 L. 10 55 0 14 A.M. H. 6 2 — 4 L. 6 27 2 28 A.M. H. 4 56 — 5 P.M. L. 23 + 5 P.M. H. 0 32 — 2 L. 11 9 + i H. 6 28 + 6 L. 6 56 + 1 P.M. H. 5 12 + 4 15 A.M. L. 49 — 4 22 A.M. H. 59 0 L. 11 30 — 1 H. 6 53 — 4 L. 7 18 — 1 P.M. L. 1 11 + 3 P.M. H. l 28 0 H. 7 17 + 6 L. 7 47 + 1 2 i MDCCCXXXVII 236 THE REV. W. WHEWELL ON THE PROGRESS OF THE Tables, &c. (Continued.) Penzance. Penzance. Penzance. Tide. Time. Diurnal Inequal. Tide. Time. Diurnal Inequal. Tide. Time. Diurnal Inequal. 1835. h m 1835. h m 1835. h m June 9 a.m. H. 2 50 — 3 June 16 a.m. L. 2 55 — 3 June 23 a.m. H. 2 55 — 2 L. 9 30 0 H. 8 30 — 7 L. 9 25 — 1 P.M. H. 3 10 + 2 P.M. L. 3 25 + 3 P.M. H. 3 20 + 2 L. 9 50 + 1 H. 9 0 + 7 L. 9 45 0 10 A.M. H. 3 30 — 1 17 a.m. L. 3 50 — 3 24 A.M. H. 3 35 — 1 L. 10 15 0 H. 9 25 — 6 L. 10 0 + 2 P.M. H. 3 55 + 2 P.M. L. 4 5 + 3 P.M. H. 3 50 + 2 L. 10 40 0 H. 10 0 + 9 L. 10 15 0 11 A.M. H. 4 20 — 1 18 A.M. L. 4 30 — 3 25 A.M. H. 4 15 — 11 L. 11 5 0 H. 10 25 — 8 L. 10 45 — 4 P.M. H. 4 50 + 2 P.M. L. 5 5 + 2 P.M. H. 4 35 — 4 L. 11 40 — 1 H. 11 10 + 6 L. 10 55 1 12 A.M. H. 5 20 — 4 19 a.m. L. 5 50 — 2 26 A.M. H. 4 50 — 1 L. 11 55 + 1 H. 11 30 — 4 L. 11 10 + 4 P.M. H. 5 40 + 3 P.M. L. 6 20 + 2 P.M. H. 5 0 + 5 13 A.M. L. 30 — 2 H. 11 55 + 4 L. 11 30 0 H. 6 5 — 4 20 A.M. L. 6 45 — 1 27 A.M. H. 5 15 — 5 P.M. L. 50 + 3 P.M. H. 35 — 5 L. 11 40 — 1 H. 6 2b + 4 L. 7 15 + 2 P.M. H. 5 25 + 2 14 A.M. L. 1 10 — 2 21 A.M. H. 55 + 4 L. 12 0 — 1 H. 6 45 — 5 L. 7 35 — 2 28 A.M. H. 5 45 — 2 P.M. L. 1 35 + 3 P.M. H. 1 10 — 3 P.M. L. 20 + 3 H. 7 15 + 6 L. 8 5 + 1 H. 6 10 + 5 15 A.M. L. 2 5 — 4 22 A.M. H. 1 55 — 1 H. 7 35 — 7 L. 8 25 — 2 P.M. L. 2 25 + 4 P.M. H. 2 30 + 2 H. 8 0 + 6 L. 9 0 + 3 Plymouth. Plymouth. Plymouth. June 9 a.m. H. 3 55 0 June 16 a.m. L. 3 11 6 June 23 a.m. H. 3 32 2 L. 10 3 0 H. 9 20 — 7 L. 9 46 — 1 P.M. H. 4 13 + 1 P.M. L. 3 34 + 3 P.M. H. 4 0 0 L. JO 20 0 H. 9 43 + 7 L. 10 5 — 1 1 0 A.M. H. 4 33 — 1 17 A.M. L. 3 43 — 3 24 A.M. H. 4 15 — 1 L. 11 0 0 H. 10 16 — 6 L. 10 13 + 5 P.M. H. 5 2 + 1 P.M. L. 4 20 + 3 P.M. H. 4 23 + 3 L. 11 43 0 H. 10 34 + 8 L. 10 40 0 11 A.M. H. 5 54 — 2 18 A.M. L. 4 34 — 3 25 A.M. H. 4 50 0 P.M. L. 1 + 1 H. 10 58 — 7 L. 11 4 — 6 H. 6 8 + 3 P.M. L. 5 8 + 2 P.M. H. 5 18 — 2 12 A.M. L. 22 — 1 H. 11 27 + 3 L. 11 25 — 2 H. 6 33 — 5 19 a.m. L. 5 36 — 2 26 A.M. H. 5 45 — 9 P.M. L. 39 + 2 P.M. H. 8 — 3 L. 11 47 + 5 H. 6 43 + 3 L. 6 13 + 1 P.M. H. 5 54 + 8 13 A.M. L. 1 5 — 5 20 A.M. H. 31 + 2 27 A.M. L. 25 + 1 H. 7 16 — 3 L. 6 40 — 1 H. 6 15 — 3 P.M. L. l 27 + 4 P.M. H. 1 5 — 1 P.M. L. 42 — 3 H. 7 24 + 4 L. 7 21 + 3 H. 6 42 + 4 14 A.M. L. l 47 — 3 21 A.M. H. 1 28 + 4 28 A.M. L. 55 0 H. 8 7 — 5 L. 7 52 — o H. 7 15 — 4 P.M. L. 2 13 + 4 P.M. H. 2 7 — 4 P.M. L. l 21 + 4 H. 8 24 + 5 L. 8 17 + 2 H. 7 25 + 8 15 A.M. L. 2 36 — 5 22 A.M. H. 2 28 — 2 H. 8 47 — 6 L. 8 41 — 2 P.M. L. 2 54 + 5 P.M. H. 3 4 + 3 H. 8 58 + 7 L. 9 21 + 4 DIURNAL INEQUALITY WAVE ALONG THE COASTS OF EUROPE 237 Tables, &c. (Continued.) Bridport. Bridport. Bridport. Tide. Time. Diurnal Inequal. Tide. Time. Diurnal Inequal. Tide. Time. Diurnal Inequal. 1835. h m 1835. h m 1835. h m June 9 a.m. H. 4 15 0 June 16 a.m. L. 4 0 0 June 23 a.m. H. 4 0 — 3 L. 10 0 + 1 H. 10 15 — 4 L. 9 30 — 1 P.M. H. 4 30 0 P.M. L. 4 0 0 P.M. H. 4 13 0 L. 10 30 — 1 H. 10 0 + 5 L. 10 0 + 2 10 A.M. H. 5 0 0 17 A.M. L. 4 15 0 24 A.M. H. 5 0 0 L. 10 45 0 H. 10 45 — 3 L. 10 30 0 P.M. H. 5 30 0 P.M. L. 4 30 0 P.M. H. 5 15 + 3 L. 11 0 0 H. 11 0 + 7 L. 11 0 — 3 11 A.M. H. 5 45 0 18 A.M. L. 5 0 0 25 A.M. H. 5 15 — 3 L. 11 30 0 H. 11 45 — 2 L. 11 15 + 3 P.M. H. 6 30 + 1 P.M. L. 5 15 + 1 P.M. H. 5 45 + 1 12 A.M. L. 30 + 1 H. 11 45 6 L. 11 45 — 4 H. 7 o — 3 19 a.m. L. 5 45 — 2 26 A.M. H. 6 0 0 P.M. L. 45 — 1 P.M. H. 15 + 2 L. 12 0 + 4 H. 7 20 + 2 L. 6 15 + 1 P.M. H. 6 15 + 7 13 A.M. L. 1 15 0 20 A.M. H. 45 + 1 27 A.M. L. 30 — l H. 8 15 — 1 L. 6 30 2 H. 6 30 — 8 P.M. L. 1 45 + 9 P.M. H. 1 15 — 9 P.M. L. 1 0 - 2 H. 8 30 — 2 L. 7 0 + 3 H. 7 0 + 4 14 A.M. L. 2 0 0 21 A.M. H. l 45 + 2 28 A.M. L. 1 15 0 H. 8 40 + 2 L. 7 15 — 1 H. 7 30 — 5 P.M. L. 2 15 — 2 P.M. H. 2 30 — 1 P.M. L. l 30 + 3 H. 9 0 + 1 L. 8 0 + 1 H. 8 0 + 7 15 A.M. L. 2 30 + 1 22 A.M. H. 3 0 0 H. 9 30 — 4 L. 8 45 — 2 P.M. L. 3 0 0 P.M. H. 3 30 + 2 I H. 9 45 + 4 L. 9 15 + 1 Cherbourg. Cherbourg. Cherbourg. June 9 a.m. H. 6 23 2 June 16 a.m. L. 6 8 7 June 23 a.m. L. 13 0 P.M. L. 49 0 H. 11 52 — 5 H. 5 58 — 1 H. 6 41 + 2 P.M. L. 6 30 + 9 P.M. L. 39 + 1 10 A.M. L. 1 20 0 17 A.M. H. 12 + 5 H. 6 18 + 1 H. 7 1 — 1 L. 7 1 — 8 24 A.M. L. 52 - 2 P.M. L. 1 40 0 P.M. H. 38 — 3 H. 6 43 — 1 H. 7 21 + 2 L. 7 20 + 9 P.M. L. 1 25 + 8 11 A.M. L. 2 9 — 1 1 8 A.M. H. 59 + 4 H. 6 40 + 5 H. 7 52 — 2 L. 7 47 — 8 25 A.M. L. 1 44 - 3 P.M. L. 2 34 + 2 P.M. H. l 40 — 3 H. 7 24 — 2 H. 8 17 + 2 L. 8 18 + 6 P.M. L. 1 49 + 2 12 A.M. L. 2 57 — 3 19 a.m. H. 2 6 + 2 H. 7 21 + 2 H. 8 43 — 5 L. 9 1 — 3 26 A.M. L. 2 29 — 3 P.M. L. 3 24 + 4 P.M. H. 2 46 + 1 H. 7 49 - 5 H. 9 4] + 7 L. 9 42 + 3 P.M. L. 2 25 + 8 13 A.M. L. 3 52 — 5 20 A.M. H. 3 19 — 1 H. 8 0 + 12 H. 9 26 — 4 L. 9 51 — 3 27 A.M. L. 2 40 — 1 P.M. L. 4 14 + 7 P.M. H. 3 51 0 H. 8 32 — 3 H. 9 47 + 4 L. 10 34 + 5 P.M. L. 3 1 + 1 1 4 A.M. L. 4 31 — 4 21 A.M. H. 4 5 + 1 H. 8 35 + 3 H. 10 21 — 4 L. 10 50 — 4 28 A.M. L. 3 31 — 4 P.M. L. 4 58 + 7 P.M. H. 4 38 0 H. 8 58 - 6 H. 10 34 + 4 L. 11 17 0 P.M. L. 3 44 + 7 15 A.M. L. 5 17 — 6 22 A.M. H. 5 7 — 1 H. 9 11 + 5 H. 11 3 — 4 L. 11 38 0 P.M. L. 5 40 + 8 P.M. H. 5 30 + 2 H. 11 21 + 4 2 i 2 238 THE REV. W. WHEWELL ON THE PROGRESS OF THE Tables, See. (Continued.) Havre. Havre. Havre. Tide. Time. Diurnal Inequal. Tide. Time. Diurnal [nequal. Tide. Time. Diurnal Inequal. 1835. h m 1835. h m 1835. h m June 9 a.m. L. 3 0 0 June 16 a.m. H. 1 15 + 4 June 23 a.m. L. 2 32 — 1 H. 7 55 - 2 L. 8 45 — 5 H. 8 1 - 1 p.m. L. 3 26 0 P.M. H. 1 55 — 4 P.M. L. 2 55 + 1 H. 8 22 + 2 L. 8 53 + 2 H. 8 32 + 2 10 A.M. L. 3 49 0 17 a.m. H. 2 11 + 3 24 A.M. L. 3 25 — 4 H. 8 45 - 3 L. 9 19 — 2 H. 8 51 — 5 P.M. L. 4 15 0 P.M. H. 3 4 — 1 P.M. L. 3 35 + 10 H. 9 16 + 3 L. 9 53 + 3 H. 9 14 + 4 11 A.M. L. 4 54 — 2 18 a.m. H. 3 13 + 2 25 A.M. L. 3 54 - 2 H. 9 39 - 2 L. 10 10 — 4 H. 9 43 — 1 P.M. L. 5 8 + 2 P.M. H. 3 53 — 1 P.M. L. 4 18 + 3 H. 10 8 + 3 L. 10 44 + 6 H. 10 11 + 2 12 A.M. L. 5 38 - 3 19 A.M. H. 4 12 0 26 A.M. L. 4 51 - 4 H. 10 21 - 4 L. 11 16 — 1 H. 9 53 — 4 P.M. L. 5 59 + 2 P.M. H. 4 51 + 1 P.M. L. 5 2 + 3 H. 10 43 + 3 L. 11 41 + 1 H. 10 36 + 13 13 A.M. L. 6 33 — 3 20 A.M. H. 5 22 — 2 27 A.M. L. 5 21 0 H. 11 17 — 2 P.M. L. 8 — 1 H. 10 25 - 2 P.M. L. 6 49 + 5 H. 6 12 + 2 P.M. L. 5 41 + 1 H. 11 41 + 3 21 A.M. L. 46 + 6 H. 10 35 + 2 14 A.M. L. 7 10 - 6 H. 6 15 — 2 28 A.M. L. 6 4 — 5 P.M. H. 7 — 4 P.M. L. 1 19 — 4 H. 11 1 - 6 L. 7 27 + 5 H. 6 41 + 1 P.M. L. 6 23 + 7 1 5 A.M. H. 21 + 3 22 A.M. L. 1 44 — 1 H. 11 13 + 4 L. 7 47 - 7 H. 7 19 — 2 P.M. H. 1 0 — 4 P.M. L. 2 1 + 1 L. 8 15 + 8 H. 7 39 + 2 Lulwortb. Lulworth. Lulworth. June 9 a.m. L. 45 +' 4 June 16 a.m. L. 6 20 15 June 23 a.m. H. 4 40 0 H. 5 38 - 6 H. 11 8 + 2 p.m. L. 30 + 1 P.M. L. 1 10 — 1 P.M. L. 6 52 + 12 H. 5 20 0 H. 6 2 + 3 H. 11 29 — 3 24 A.M. L. 55 - 2 10 A.M. L. 1 45 - 2 17 A.M. L. 7 20 14 H. 5 45 0 J H. 6 36 — 5 H. 11 59 + 4 P.M. L. 1 10 + 5 P.M. L. 2 10 + 4 P.M. L. 7 45 + 13 H. 5 59 - 2 H. 6 46 + 2 18 A.M. H. 32 — 4 25 A.M. L. 1 40 - 5 11 A.M. L. 2 40 — 4 L. 8 10 -12 H. 6 30 0 H. 7 25 0 P.M. H. 50 + 4 P.M. L. 2 1 + 4 P.M. L. 3 7 + 4 L. 8 30 + 9 H. 6 59 0 H. 7 58 + 1 19 a.m. H. 1 10 — 2 26 A.M. L. 2 38 — 5 12 A.M. L. 3 34 - 5 L. 8 52 — 4 H. 7 38 + 6 H. 8 20 — 1 P.M. H. 1 40 + 6 P.M. L. 2 58 + ^ P.M. L. 3 49 + 8 L. 9 10 + 3 H. 7 59 + 8 H. 8 39 0 20 A.M. H. 2 12 — 8 27 A.M- L. 3 15 _ 6 13 A.M. L. 4 12 — 11 L. 9 35 — 2 H. 8 17 — 2 H. 8 52 + 2 P.M. H. 2 38 + 3 P.M. L. 3 40 + 11 P.M. L. 4 36 + 5 L. 10 12 + 9 H. 8 25 F 1 H. 9 18 0 21 A.M. H. 2 59 — 3 28 A.M. L. 3 55 - 9 14 A.M. L. 5 5 — 4 L. 10 52 — 3 H. 8 40 — 1 H. 9 55 - 6 P.M. H. 3 35 + 2 P.M. L. 4 15 + 8 P.M. L. 5 30 + 8 L. 11 10 + 2 H. 8 50 + 2 H. 10 25 — 2 22 A.M. H. 4 5 — 2 15 A.M. L. 5 53 -12 L. 11 40 0 H. 10 39 + 4 P.M. H. 4 25 + 4 P.M. L. 6 5 + 13 L. 11 55 — 1 H. 10 50 — 3 DIURNAL INEQUALITY WAVE ALONG THE COASTS OF EUROPE 239 Tables, &c. (Continued.) Portsmouth. Portsmouth. Portsmouth. Tide. Time. Diurnal Inequal. Tide. Time. Diurnal Inequal. Tide. Time. Diurnal Inequal. 1835. h m 1835. h m 1835. h m June 9 a.m. L. 2 20 + 4 June 16 a.m. H. 3 10 — 2 June 23 a.m. L, 2 15 — 1 H. 9 55 — 2 L. 8 10 — 6 H. 9 37 0 p.m. L. 2 55 0 P.M. H. 3 35 + 2 p.m. L. 2 37 + 2 H. 10 15 + 3 L. 8 35 + 6 H. 9 57 0 10 A.M. L. 3 15 — 2 17 A.M. H. 4 0 — 4 24 A.M. L. 2 57 — 3 H. 10 45 — 3 L. 9 0 — 6 H. 10 17 + 6 P.M. L. 3 45 + 2 P.M. H. 4 35 + 9 P.M. L. 3 17 + 2 H. 11 10 + 2 L. 9 35 + 6 H. 10 39 - 6 11 A.M. L. 4 11 — 1 18 A.M. H. 5 0 — 6 25 A.M. L. 3 39 0 H. 11 32 0 L. 10 0 — 8 H. 10 55 — 5 P.M. L. 4 33 + 1 P.M. H. 5 35 + 4 F.M. L. 3 55 - 3 1 2 A.M. H. 11 + 1 L. 10 38 0 H. 11 10 + 3 L. 5 11 — 2 19 a.m. H. 6 2 — 3 26 A.M. L. 4 10 - 7 P.M. H. 34 — 2 L. 11 2 + 1 H. 11 35 + 1 L. 5 34 + 1 P.M. H. 6 40 + 5 P.M. L. 4 36 + 10 13 A.M. H. 48 + 2 L. 11 40 — 1 H. 11 57 0 L. 5 50 0 20 A.M. H. 7 10 — 9 27 A.M. L. 5 2 + 5 P.M. H. 1 10 + 3 P.M. L. 10 — 1 P.M. H. 21 — 1 L. 6 10 — 2 H. 7 45 + 5 L. 5 21 — 2 14 A.M. H. 1 36 + 1 21 A.M. L. 45 + 1 28 A.M. H. 41 + 2 L. 6 37 0 H. 7 55 — 4 L. 5 41 - 6 P.M. H. 2 0 0 P.M. L. 0 55 — 1 P.M. H. 1 0 — 2 L. 7 0 + 4 H. 8 22 -t- 1 L. 6 0 + 3 15 A.M. H. 2 22 — 1 22 A.M. L. 1 23 — 2 L. 7 22 — 6 H. 8 47 — 1 P.M. H. 2 45 + 3 P.M. L. 1 47 + 1 L. 7 45 + 6 H. 9 15 0 Port Magee. Port Magee. Port Magee. June 9 a.m. H. l 50 3 June 16 a.m. L. 1 40 — 3 June 23 a.m. H. 2 20 — 2 L. 8 0 — 2 H. 8 15 — 4 L. 8 43 — 1 p.m. H. 2 30 + 2 P.M. L. 2 30 + 1 P.M. H. 2 34 + 1 L. 8 40 + 2 H. 8 30 + 4 L. 8 53 + 12 10 A.M. H. 2 52 — 2 17 a.m. L. 2 43 — 2 24 A.M. H. 3 10 + 1 L. 9 7 — 1 H. 9 10 — 3 L. 9 23 + 10 P.M. H. 3 18 + 2 P.M. L. 3 18 + 9 P.M. H. 3 40 + 4 L. 9 32 0 H. 9 30 + 1 L. 9 55 + 3 11 A.M. H. 3 47 — 1 18 A.M. L. 3 40 — 1 25 A.M. H. 4 0 2 L. 9 57 + 1 H. 10 0 — 1 L. 10 10 — i P.M. H. 4 9 + 2 P.M. L. 4 15 + 1 P.M. H. 4 0 + i L. 10 20 — 1 H. 10 20 + 1 L. 10 15 + 5 12 A.M. H. 4 30 — 2 19 a.m L. 4 35 — 2 26 A.M. H. 4 18 — 5 L. 10 41 + 3 H. 11 5 — 2 L. 10 30 + 3 P.M. H. 4 54 + 3 P.M. L. 5 20 + 11 P.M. H. 4 24 + 3 L. 11 9 5 H. 11 20 + 3 L. 10 30 — 2 13 A.M. H. 5 19 — 3 20 A.M. L. 5 30 + 5 27 A.M. H. 4 43 — 3 L. 11 30 + 6 H. 12 0 — 2 L. 10 58 + 1 P.M. H. 5 44 + 4 P.M. L. 6 20 0 P.M. H. 5 17 + ^ L. 12 0 5 21 A.M. H. 40 0 L. 11 25 — 1 14 A.M. H. 6 10 2 L. 6 45 — 4 28 A.M. H. 5 30 — 3 P.M. L. 17 + 6 P.M. H. 1 10 0 L. 11 47 + 3 H. 6 25 + 2 L. 7 15 + 1 P.M. H. 5 45 + 2 15 A.M. L. 33 — 5 22 A.M. H. l 35 0 H. 6 53 — 2 L. 7 45 — 1 P.M. L. 1 15 + 8 P.M. H. l 45 + 1 H. 7 10 + 3 L. 7 50 + 1 240 THE REV. W. WHEWELL ON THE PROGRESS OF THE Tables, &c. (Continued.) Doonkegh an. Doonkeghan. Doonkeghan. Tide. Time. Diurnal Inequal. Tide. Time. Diurnal Inequal. Tide. Time. Diurnal Inequal. 1835. h m 1835. h m 1835. h m June 9 a.m. H. 3 24 - 1 June 16 a.m. L. 3 0 - 6 June 23 a.m. H. 3 30 — 2 L. 9 34 — 5 H. 9 20 -12 L. 9 42 — 4 P.M. H. 3 49 + 1 P.M. L, 3 25 + 9 P.M. H. 3 45 + 1 L. 9 58 + 7 H. 10 4 + 14 L. 10 2 + 4 10 A.M. H. 4 2 — 1 17 A.M. L. 4 20 - 7 24 A.M. H. 4 10 — 1 L. 10 2 — 2 H. 10 30 - 6 L. 10 15 0 P.M. H. 4 36 + 3 P.M. L. 4 15 + 6 P.M. H. 4 27 + 4 L. 10 26 + 2 H. 10 50 + 9 L. 10 37 0 11 A.M. H. 4 55 — 4 18 A.M. L. 5 11 — 5 25 A.M. H. 4 38 11 L. 11 1 — 3 H. 11 40 -12 L. 10 45 — 2 P.M. H. 5 29 + 5 P.M. L. 5 54 + 5 P.M. H. 5 0 + 1 L. 11 29 + 1 19 A.M. H. 10 + 8 L. 11 9 + 1 12 A.M. H. 5 50 _ 6 L. 6 17 - 6 26 A.M. H. 5 17 — 2 P.M. L. 11 43 + 2 P M. H. 28 - 7 L. 11 5 + 3 H. 6 3 + 9 L. 6 30 + 9 P.M. H. 5 27 + 6 13 A.M. L. 15 — 3 20 A.M. H. 35 + 9 L. 11 40 — 3 H. 6 26 - 8 L. 7 15 - 6 27 A.M. H. 5 51 — 9 P.M. L. 18 + 4 P.M. H. 1 50 - 6 L. 11 40 + 1 H. 6 46 + 9 L. 8 3 + 5 P.M. H. 5 52 + 9 14 A.M. L. 1 14 - 6 21 A.M. H. 2 5 + 3 28 A.M. L. 20 — 2 H. 7 40 - 9 L. 8 10 - 6 H. 6 20 — 8 P.M. L. 1 11 + 5 P.M. H. 2 20 — 3 P.M. L. 20 + 9 H. 7 40 + 12 L. 8 35 + 5 H. 6 27 -f 7 15 A.M. L. 1 57 - 6 22 A.M. H. 2 45 + 3 H. 8 16 -12 L. 9 0 + 6 P.M. L. 2 12 + 6 P.M. H. 3 30 + 1 II. 8 32 + 13 L. 9 20 + 6 Sligo. Sligo. Sligo. June 9 a.m. H. 3 45 + 1 June 16 a.m. L. 3 20 - 6 June 23 a.m. H. 3 55 0 L. 10 0 - 6 H. 9 40 — 15 L. 10 10 — 6 P.M. H. 4 20 — 1 P.M. L. 3 25 + 4 P.M. H. 4 20 0 L. 10 30 + 6 H. 9 50 + 15 L. 10 30 + 4 10 A.M. H. 4 40 0 17 A.M. L. 4 10 — 3 24 A.M. H. 4 35 + 6 L. 10 45 — 3 H. 9 55 — 15 L. 10 40 0 P.M. H. 5 15 + 2 P.M. L. 4 20 + 2 P.M. H. 4 50 + 9 L. 11 25 + 4 H. 10 40 + 10 L. 11 0 0 11 A.M. H. 5 40 — 2 18 A.M. L. 5 0 - 2 25 A.M. H. 5 10 — 4 L. 11 40 0 H. 11 30 -10 L. 11 20 0 P.M. H. 6 0 + 4 P.M. L. 5 50 + 5 P.M. H. 5 30 + 3 12 A.M. L. 10 0 19 a.m. H. 10 + 13 L. 11 45 0 H. 6 20 — 5 L. 6 30 — 5 26 A.M. H. 6 0 — 2 P.M. L. 30 0 P.M. H. 1 0 -11 P.M. L. 10 0 H. 6 45 + 7 L. 7 10 + 8 H. 6 20 + 7 13 A.M. L. 1 0 0 20 A.M. H. 1 30 + 13 27 A.M. L. 30 0 H. 7 15 — 8 L. 7 50 — 4 H. 6 35 — 9 P.M. L. 1 15 + 3 P.M. H. 2 0 -11 P.M. L. 35 0 H. 7 30 + 9 L. 8 0 + 2 H. 6 45 + 19 14 A.M. L. 1 40 - 6 21 A.M. H. 2 15 + 9 28 A.M. L. 1 0 0 H. 8 0 -10 L. 8 25 — 5 H. 7 10 — 8 P.M. L. 2 0 + 3 P.M. H. 2 35 - 6 P.M. L. 1 15 0 H. 8 15 + 11 L. 8 50 + 1 H. 7 30 + 7 15 A.M. L. 2 15 - 3 22 A.M. H. 3 10 + 9 H. 8 45 -13 L. 9 25 - 1 P.M. L. 2 30 + 3 P.M. H. 3 30 0 H. 9 0 + 14 L. 9 40 + 4 DIURNAL INEQUALITY WAVE ALONG THE COASTS OF EUROPE, 241 Tables, &c. (Continued.) Port Ballynass. Port Bally lass. Port Ballynass. Tide. Time. Diurnal Inequal. Tide. Time. Diurnal Inequal. Tide. Time. Diurnal Inequal. 1835. h m 1835. h m 1835. h m June 9 a.m. H. 4 30 — 1 June 16 a.m. L. 3 54 0 June 23 a.m. H. 4 12 0 L. 11 10 - 2 H. 10 0 — 12 L. 10 18 0 P.M. H. 4 45 + 1 P.M. L. 4 30 0 P.M. H. 4 25 0 L. 11 15 + 2 H. 10 30 + 15 L. 10 30 + 1 10 A.M. H. 5 0 — 3 17 A.m. L. 4 43 + 1 24 A.M. H. 4 37 + 3 L. 11 55 — 1 H. 10 58 — 5 L. 10 45 — 1 P.M. H. 5 40 + 2 P.M. L. 4 50 — 2 P.M. H. 4 50 — 1 11 A.M. L. 10 + 1 H. 11 25 + 3 L. 11 2 + 3 H. 6 5 0 18 A.M. L. 5 30 0 25 A.M. H. 5 20 + 2 P.M. L. 56 0 H. 11 50 — 5 L. 11 30 — 4 H. 6 20 + 1 P.M. L. 6 2 0 P.M. H. 5 35 — 5 12 A.M. L. 54 0 19 A.M. H. 30 + 10 L. 11 55 0 H. 6 45 - 2 L. 6 20 0 26 A.M. H. 6 10 + 15 P.M. L. 1 20 0 P.M. H. 56 — 4 P.M. L. 13 — 1 H. 6 57 + 4 L. 6 50 0 H. 6 20 + 1 13 A.M. L. 1 42 + 1 20 A.M. H. 1 18 + 7 27 A.M. L. 30 + 3 H. 7 35 - 6 L. 6 35 + l H. 6 45 — 1 P.M. L. 2 1 — 1 P.M. H. 1 55 — 5 P.M. L. 54 0 H. 7 50 + 7 L. 7 40 — 2 H. 6 40 + 3 14 A.M. L. 2 25 — l 21 A.M. H. 2 15 + 4 28 A.M. L. 1 10 0 H. 8 10 — 4 L. 8 0 + 1 H. 7 20 — 4 P.M. L. 2 35 0 P.M. H. 2 45 - 3 P.M. L. 1 18 0 H. 8 34 + 5 L. 8 34 - 1 H. 7 25 + 5 15 A.M. L. 3 0 0 22 A.M. H. 3 5 + 3 H. 9 2 - 4 L. 9 25 + 2 P.M. L. 3 1 — 1 P.M. H. 3 36 — 1 H. 9 25 + 7 L. 9 40 0 Scrabsters. Scrabsters. Scrabsters. June 9 a.m. L, 20 + 10 June 16 a.m. H. 15 + 9 June 23 a.m. L. 2 + 1 H. 6 45 - 0 L. 6 45 - 9 H. 6 35 + 1 P.M. L. 45 - 6 P.M. H. 1 0 - 6 P.M. L. 40 — 2 H. 7 0 0 L. 7 0 + 14 H. 6 50 — O | 10 A.M. L. l 10 + 5 17 A.m. H. l 20 + 10 24 A.M. L. 1 15 + 1 1 H. 7 30 0 L. 7 40 — 15 H. 7 25 + 1 P.M. L. 1 45 — 4 P.M. H. 1 50 — 13 P.M. L. l 40 0 H. 8 0 0 L. 7 50 + 4 H. 7 45 + 6 11 A.M. L. 2 0 + 8 18 A.M. H. 2 10 + 9 25 A.M. L. 2 0 0 i H. 8 15 — 1 L. 8 40 — 5 H. 8 0 — 3 P.M. L. 2 25 — 3 P.M. H. 2 50 — 4 P.M. L. 2 15 0 j H. 8 40 + 1 L. 9 0 + 6 H. 8 25 + 1 12 A.M. L. 2 55 - 6 19 A.M. H. 3 20 + 4 26 A.M. L. 2 35 — 1 1 H. 9 20 - 2 L. 9 20 -10 H. 8 40 — 3 P.M. L. 3 10 + 3 P.M. H. 3 45 — 5 P.M. L. 2 50 + 4 H. 9 45 + 5 L. 9 45 + 11 H. 9 0 + 7 ! 1 3 A.M. L. 3 45 — 3 20 A.M. H. 4 10 + 8 27 A.M. L. 3 0 — 2 i H. 10 10 — 2 L. 10 30 - 7 H. 9 15 — 4 P.M. L. 4 15 + 3 P.M. H, 4 45 - 6 P.M. L. 3 15 — 1 H. 10 30 + 1 L. 10 50 + 3 H. 9 30 4" 3 i 14 A.M. L. 4 40 — 4 21 A.M. H. 5 10 0 28 A.M. L. 3 38 — 5 H. 11 0 — 5 L. 11 20 — 5 H. 9 45 — 4 I P.M. L. 5 10 + 9 P.M. H. 5 35 + 2 P.M. L. 3 55 + 4 I H. 11 20 + 9 L. 11 45 + 9 H. 10 3 + 6 15 A.M. L. 5 35 — 11 22 A.M. H. 5 50 0 H. 11 50 - 9 L. 11 55 — 1 P.M. L. 6 0 + 9 P.M. H. 6 15 0 242 THE REV. W. WHEWELL ON THE PROGRESS OF THE Tables, &c. (Continued.) Buckie. Buckie. Buckie. Tide. Time. Di urnal In equal. Tide. Time. Diurnal Inequal. Tide. Time. Diurnal Inequal. 1835. h m 1835. h m 1835. h m June 9 a.m. L. 4 10 + 3 June 16 a.m. H. 3 30 + 8 June 23 a.m. L, 4 0 + 5 H. 10 30 0 L. 10 0 - 7 H. 10 0 — 2 P.M. L. 4 30 - 3 P.M. H. 4 5 — 5 P.M .' L. 4 20 — 1 H. 11 0 + 1 L. 10 15 + 17 H. 10 20 — 2 10 A.M. L. 5 0 + 4 17 a.m. H. 4 0 + 9 24 A.M. L. 4 50 — 1 H. 11 15 0 L. 11 10 -10 H. 10 35 0 P.M. L. 5 20 - 2 P.M. H. 5 10 -11 P.M. L. 5 0 + 2 H. 11 45 0 L. 11 20 + 10 H. 11 0 0 11 A.M. L. 6 0 0 1 8 A.M. H. 5 25 + 1 25 A.M. L. 5 30 4“ 2 P.M. H. 5 0 P.M. L. 10 - 6 H. 11 10 — 1 L. 6 25 0 H. 6 10 — 1 P.M. L. 5 45 0 12 A.M. H. 20 + 1 19 A.M. L. 25 + 12 H. 11 40 + 4 L. 6 40 — 3 H. 6 15 + 1 26 A.M. L. 6 10 — 2 P.M. H. 40 — 1 P.M. L. 1 0 - 9 P.M. H. 10 — 2 L. 7 0 + 5 H. 7 15 — 5 L. 6 20 + 2 13 A.M. H. l 5 0 20 A.M. L. l 30 + 6 27 a.m. H. 30 + 3 L. 7 20 - 5 H. 7 35 + 7 L. 6 40 0 P.M. H. l 30 + 1 P.M. L. 2 0 - 7 P.M. H. 35 — 3 L. 7 40 + 9 H. 8 0 - 6 L. 7 0 0 1 4 A.M. H. l 50 + 2 21 A.M. L. 2 20 + 3 28 A.M. H. l 10 + 3 L. 8 20 - 9 H. 8 15 0 L. 7 20 — 6 P.M. H. 2 20 — 4 P.M. L. 2 45 — 5 P.M. H. 1 40 — 2 L. 8 35 + 8 H. 8 35 + 1 L. 7 40 + 4 15 A.M. H. 2 35 + 4 22 A.M. L. 3 10 + 5 L. 9 5 -10 H. 9 0 - i P.M. H. 3 15 — 5 P.M. L. 3 20 + 4 L. 9 15 + 10 H. 9 45 + 4 North Berwick. North Berwick. North Berwick. June 9 a.m. H. 23 0 June 16 a.m. H. 6 16 + 3 June 23 a.m. H. 26 + 4 L. 6 36 + 7 P.M. L. 23 — 10 L. 6 40 + 4 P.M. H. 48 + 1 H. 6 45 — 5 P.M. H. 47 — 3 L. 7 0 — 4 17 a.m. L. 53 + 16 L. 6 54 — 4 10 A.M. H. l 11 0 H. 7 10 + 9 24 A.M. H. 1 12 0 L. 7 21 + 2 P.M. L. l 22 — 11 L. 7 15 — 3 P.M. H. 1 40 + 1 H. 7 46 - 6 P.M. H. l 29 0 L. 7 43 - 2 18 A.M. L. l 54 + 8 L. 7 33 0 11 A.M. H. 2 11 - 1 H. 8 10 0 25 A.M. H. 1 50 0 L. 8 15 + 1 P.M. L. 2 24 — 10 L. 7 54 + 1 P.M. H. 2 34 + 2 H. 8 45 + 6 P.M. H. 2 0 + 1 A L. 8 37 0 19 a.m. L. 2 58 + 15 L. 8 5 + 1 12 A.M. H. 3 0 — 3 H. 8 58 + 3 26 A.M. H. 2 19 ° i L. 9 4 - 3 P.M. L. 3 24 - 6 L. 8 24 — 1 P.M. H. 3 24 + 2 H. 9 44 — 5 P.M. H. 2 41 — i L. 9 32 + 4 20 A.M. L. 3 50 + 6 L. 8 44 0 13 A.M. H. 3 46 — 2 H. 10 16 + 4 27 a.m. H. 3 4 + 1 L. 9 56 - 6 P.M. L. 4 22 — 5 L. 9 5 — 3 P.M. H. 4 12 + 3 H. 10 40 — 2 P.M. H. 3 20 0 L. 10 16 + 8 21 A.M. L. 5 0 + 6 L. 9 17 + 5 14 A.M. H. 4 34 0 H. 11 10 — 3 28 A.M. TI. 3 36 0 L. 10 41 -10 P.M. L. 5 16 - 9 L. 9 38 — 9 P.M. H. 4 57 0 H. 11 32 + 3 P.M. H. 3 58 0 L. 11 4 + 10 22 A.M. L. 5 37 + 5 L. 10 0 + 4 15 A.M. H. 5 24 0 H. 11 57 - 3 L. 11 32 - 9 P.M. L. 6 6 - 2 P.M. H. 5 50 - 2 L. 11 56 + 10 DIURNAL INEQUALITY WAVE ALONG THE COASTS OF EUROPE 243 Tables, &c. (Continued.) Berwick-upon-Tweed. Berwick-upon- T weed. Berwick- upon -Tweed. Tide. Time. Diurnal Tide. Time. Diurnal Tide. Time. Diurnal lnequal. lnequal. lnequal. 1835. h m 1835. h m 1835. h m June 9 a.m. H. 27 — 3 June 16 a.m. H. 6 25 + 5 June 23 a.m. H. 56 + 5 L. 6 37 + 7 P.M. L. 35 -10 L. 7 0 + 4 p.m. H. 49 + 2 H. 7 3 — 4 P.M. H. l 4 — 4 L. 7 5 — 5 17 a.m. L. 1 8 + 14 L. 7 4 — 3 10 A.M. H. l 25 0 H. 7 33 + 8 24 A.M. H. 1 30 + 2 L. 7 32 + 3 P.M. L. l 36 — 11 L. 7 40 0 P.M. H. 1 44 0 H. 8 10 - 6 P.M. H. l 54 — 1 L. 8 4 — 3 18 A.M. L. 2 10 + 11 L. 8 0 + 1 11 A.M. H. 2 14 0 H. 8 30 0 25 A.M. H. 2 17 + 1 L. 8 26 + 1 P.M. L. 2 35 — 8 L. 8 20 + 1 P.M. H. 2 30 0 H. 9 5 + 4 P.M. H. 2 23 — 1 L. 8 45 — 1 19 A.M. L. 2 37 + 2 L. 8 30 + 2 12 A.M. H. 2 47 — 1 H. 9 15 + 7 26 A.M. H. 2 29 + 2 L. 9 15 — 2 P.M. L. 3 4 — 3 L. 8 55 — 3 P.M. H. 3 15 + 1 H. 9 40 — 4 P.M. H. 2 45 — 3 L. 9 30 + 3 20 A.M. L. 4 10 + 6 L. 9 5 + 2 13 A.M. H. 3 30 — 1 H. 10 7 + 4 27 a.m. H. 3 8 + 3 L. 10 7 — 5 P.M. L. 4 35 - 6 L. 9 20 - 3 P.M. H. 4 20 4- 2 H. 10 45 — 3 P.M. H. 3 28 - 2 L. 10 28 + 9 21 A.M. L. 4 48 + 5 L. 9 35 + 5 14 A.M. H. 4 50 0 H. 11 15 — 1 28 A.M. H. 4 0 0 L. 10 45 — 7 P.M. L. 5 5 — 10 L. 9 46 - 7 P.M. H. 5 19 0 H. 11 55 + 5 P.M. H. 4 20 0 L. 11 2 + 6 22 A.M. L. 5 47 + 6 L. 10 5 + 6 15 A.M. H. 5 33 + 2 P.M. H. 25 — 3 L. 11 32 — 7 L. 6 20 — 3 P.M. H. 6 5 — 4 L. 12 0 + 12 Clay Hole. Clay Hole. Clay Hole. June 9 a.m. H. 4 50 4 June 16 a.m. L. 4 13 + 8 June 23 a.m. H. 4 25 + 6 L. 10 55 + 7 H. 10 10 + 8 L. 10 57 + 10 P.M. H. 5 0 + l P.M. L. 5 5 — 8 P.M. H. 4 50 — 3 L. 12 0 — 5 H. 11 0 — 15 L. 10 50 — 1 10 a.m. H. 5 33 0 17 A.M. L. 5 0 + 7 24 a.m. H. 5 5 0 P.M. L. 8 + 6 H. 10 50 + 18 L. 11 35 + 1 H. 5 53 + 1 P.M. L. 6 5 — 5 P.M. H. 5 25 0 11 A.M. L. 48 — 3 18 A.M. H. 5 -16 L. 11 45 - 2 H. 6 18 — 1 L 5 40 + 9 25 a.m. H. 5 55 — 3 P.M. L. 55 + 2 P.M. H. 1 + 3 P.M. L. 1 — 1 H. 6 46 + 1 L. 6 35 -10 H. 6 10 + 14 12 A.M. L. 1 33 — 2 19 a.m. H. 1 5 — 4 26 A.M. L. 35 + 15 H. 7 3 0 L. 6 40 + 27 H. 6 20 — 2 P.M. L. l 50 0 P.M. H. 50 + 7 P.M. L. 43 — 8 H. 7 40 — 1 L. 7 35 — 4 H. 6 45 — 1 13 A.M. L. 2 20 0 20 A.M. H. 2 15 — 20 27 A.M. L. 56 + 16 H. 7 53 + 1 L. 7 45 + 4 H. 6 59 + 4 P.M. L. 2 45 0 P.M. H. 2 20 + 4 P.M. L. 1 35 + 2 H. 8 23 0 L. 8 48 - 6 H. 7 35 2 14 A.M. L. 3 0 + 6 21 A.M. H. 2 55 — 4 28 A.M. L. l 35 — 4 H. 8 45 + 1 L. 8 55 + 6 H. 7 55 0 P.M. L. 3 35 — 10 P.M. H. 3 2 — 2 P.M. L. 2 13 — 8 H. 9 23 — 4 L. 9 37 -11 H. 8 13 0 15 A.M. L. 3 30 + 8 22 A.M. H. 3 47 + 5 H. 9 30 + 6 L. 10 7 + 6 P.M. L. 4 22 — 7 P.M. H. 4 7 - 8 H. 10 15 — 9 L. 10 17 — 3 2 K MDCCCXXXVII 244 THE REV. W. WHEWELL ON THE DIURNAL INEQUALITY WAVE. Tables, &c. (Continued.) Uzon. Uzon. Uzon. Tide. Time. Diurnal Inequal. Tide. Time. Diurnal Inequal. Tide. Time. Diurnal Inequal. 1835. h 1T1 1835. h m 1835. h m June 9 a.m. H. 3 0 June 16 a.m. H. 5 45 0 June 23 a.m. L. 5 59 + 3 L. 6 5 + 5 L. 11 48 - 4 P.M. H. 22 + 6 P.M. H. 17 0 P.M. H. 6 32 - 7 L. 6 35 — 2 L. 6 26 — 5 17 a.m. L. 6 + 13 24 A.M. H. 33 — 1 10 A.M. H. 45 0 H. 6 38 + 9 L. 6 47 0 L. 6 52 + 3 P.M. L. 57 -12 P.M. H. 43 — 2 P.M. H. 1 6 + 1 H. 7 35 - 8 L. 7 6 + 2 L. 7 16 — 1 18 A.M. L. 1 12 + 8 25 A.M. H. l 15 + 1 11 A.M. H. l 25 — 1 H. 7 47 + 1 L. 7 26 — 2 L. 7 39 + 1 P.M. L. 1 46 - 8 P.M. H. l 25 — 1 P.M. H. l 49 + 2 H. 8 40 + 5 L. 7 44 + 2 L. 8 9 + 1 19 a.m. L. 2 24 + 16 26 A.M. H. 1 46 0 12 A.M. H. 2 15 — 2 H. 8 43 + 5 L. 8 5 — 2 L. 8 31 — 3 P.M. L. 3 10 - 7 P.M. H. 2 10 — 2 P.M. H. 2 44 + 1 H. 9 25 — 5 L. 8 14 + 3 L. 8 52 + 4 20 A.M. L. 3 29 + 7 27 A.M. H. 2 26 + 2 13 A.M. H. 3 3 — 1 H. 9 27 + 2 L. 8 33 — 4 L. 9 22 — 6 P.M. L. 3 55 - 6 PM. H. 2 45 — 1 P.M. H. 3 36 + 1 H. 10 40 — 2 L. 8 47 + 4 L. 9 46 + 9 21 A.M. L. 4 23 + 5 28 A.M. H. 2 57 0 14 A.M. H. 3 55 — 2 H. 10 25 0 L. 9 14 — 7 L. 10 11 — 10 P.M. L. 4 49 - 9 P.M. H. 3 31 0 P.M. H. 4 37 — 3 H. 11 42 + 5 L. 9 21 + 9 L. 10 38 + 9 22 A.M. L. 5 18 + 6 15 A.M. H. 4 48 — 3 H. 11 30 — 4 L. 10 55 — 11 P.M. L. 5 40 - 2 P.M. H. 5 30 + 6 H. 11 50 + 2 L. 11 24 + 8 [ 245 ] XV. On the Connexion between the Phenomena of the Absorption of Light, and the Colours of thin Plates. By Sir David Brewster, K. II. LL.D. F.R.S. Received May 9, — Read May 11, 1837. Since the phenomena of the absorption of light by coloured media began to be studied with attention, various philosophers have regarded them as inexplicable by the theory of the colours of thin plates, and have consequently regarded Sir Isaac Newton’s theory of the colours of natural bodies as either defective in generality, or altogether unfounded. Mr. Delaval* was the first person who brought an extensive series of experiments to bear upon this subject. Dr. Thomas Young 'f- considered it “ impossible to suppose the production of natural colours perfectly identical with those of thin plates,” unless the refractive density of the particles of colouring bodies was at least twenty or thirty times as great as that of glass or water, which he con- sidered as “ difficult to believe with respect to any of their arrangements constituting the diversities of material substances.” Sir John Herschel has expressed a still more decided opinion upon this subject. He regards “ the speculations of Newton on the colours of natural bodies” as only “a premature generalization,” and “limited to a comparatively narrow range ; while the phenomena of absorption, to which he considers the great majority of natural colours as referable, have always appeared to him to constitute a branch of photology sui generis ^.” The general opinion advanced by these three philosophers I have long entertained § ; and with the view of supporting them I have analysed a great variety of colours which are exhibited by the juices of plants. In a paper “ On the Colours of Natural Bodies ||,” I have shown that the green colour of plants, the most prevalent of all the colours of natural bodies, in place of being a green of the third order, as Newton and his com- mentators assert, is a colour of no order whatever, and having in its composition no relation at all to the colours of thin plates. In arriving at these conclusions, however, and drawing a distinct line between the phenomena of absorption and those of thin plates, two classes of facts are compared under very different circumstances. In the one case philosophers have studied in cumulo the result of the successive actions of an infinite number of the colorific parti- cles upon the intromitted light, whereas in the other case they have observed only the * Manchester Memoirs, vol. ii. p. 131. f Ed. Nat. Phil. vol. i. p. 469, 4S1. and vol. ii. p. 63S. | London and Edinburgh Philosophical Magazine, December 1833, vol. iii. p. 401. See also his Treatise on Light, Encyc. Metrop. p. 580, 581. § Life of Newton, chap. vii. || Edinburgh Transactions, vol. xii. 2 K 2 246 SIR DAVID BREWSTER ON THE CONNEXION BETWEEN CERTAIN colour of a single particle, whose thickness is equal to that of the films of air, water, glass and mica submitted to experiment. The impracticability of combining a number of such films, and studying their united action upon light, was doubtless the reason which prevented natural philosophers from bringing the two series of facts under the same conditions. Sir Isaac Newton, indeed, had spoken so confidently of the result of such a combination, as to discourage any attempts to effect it ; and it is a singular fact that his successors have never called in question his bold though ingenious as- sumption. “ If a thinned or plated body,” says he, [ 253 ] XVI. On the Development and Extinction of regular doubly refracting Structures in the Crystalline Lenses of Animals after Death. By Sir David Brewster, K.J1. LL.D. F.R.S. 8fc. fyc. Received May 10, — Read 1st June, 1837. Since the year 1816, when I communicated to the Royal Society an account of the doubly refracting structures which exist in the crystalline lenses of fishes and other animals, I have examined a great variety of recent lenses, with the view of ascertain- ing the origin of these structures, the order of their succession in different lenses, and the purpose which they answered in the animal ceconomy. Although I had found that in the lenses of the cod, the salmon, the haddock, the frog-fish, the skate, and several other fishes there were three structures, the innermost of which had negative double refraction, the next positive , and the outermost negative double re- fraction, yet in the lenses of animals the greatest discrepancies presented themselves. In every case, however, excepting one, I have found the central structure in all qua- drupeds* to be positive, while it is always negative in fishes when there are three structures, but this positive structure sometimes existed alone, with faint traces of a negative structure ; sometimes it was followed by another positive structure, separated from the first by a black neutral circle, in which the double refraction disappeared. Sometimes these two positive structures were succeeded by an external negative struc- ture. Sometimes the central and external positive structures were separated by a negative structure, and at other times the lens exhibited four structures, a negative and a positive one alternating. As these discrepancies appeared in the lenses of animals of the same species, I conceived that they were owing to differences of age or sex, or to some change in the health of the animal. I was therefore led to make new observations in reference to these probabilities, and to observe the phenomena with additional attention when the structure differed from that which was most common. In these observations I sometimes noticed in the dark or neutral line, which separated two positive structures, something like a trace of an intervening structure, which was either about to disappear, or about to be developed. This conjecture was confirmed by observations on the lenses of a cow eleven years old. The lenses after being carefully taken out, were freed from the adhering portions of the vitreous humour by the gentle application of blotting paper, so as not to disturb their internal structure. The lenses were elliptical. Their longest diameter was 0*774 inch, their shortest diameter 0*747 inch, and their thickness 0*513 of an inch. The first lens which I exposed to polarized light was in the highest perfection, and the symmetry of the optical figure unusually beautiful. I have represented it in * Excepting the hare. See Phil. Trans. 1836, p. 37. 2 L 2 254 SIR DAVID BREWSTER ON THE CHANGES IN THE STRUCTURE Plate XV. fig1. 1., in which only two structures, or two series of positive sectors, are visible *. The lens was now a day old, and there seemed to be a faint light within the two black rings, especially in the outer one, which was either the remains of an old, or the germ of a new structure. If this were the case, then the anomalous combination of two positive structures would be converted into a combination of four structures, in which a negative and a positive one alternated. On the following day I prepared the other lens with the same care, and found my conjecture completely verified. In the middle black ring, which was distinctly brownish in the first lens, the negative structure had evidently commenced at one part, and the colour of the whole ring was a brighter brown than in the first lens. In the outer black ring another negative structure had also appeared, and had ad- vanced considerably upon the positive structure. These phenomena I have repre- sented in fig. 2., where the four structures are distinctly seen, the second being a faint blue of the first order. On the third day the two new structures had become more prominent. The structure No. 2, now a pale white of the first order, was com- pletely developed, having encroached upon and almost obliterated the third structure. The structure No. 4, which was not in existence on the first day, had now the maxi- mum tint, namely a bright white of the first order. On the fourth day the struc- tures No. 2 and 4, which at first were not in existence, are now the structures with the maximum tints, and No. 3, which had the maximum tint, is now almost oblite- rated, a little faint brown light remaining in one of the quadrants. On the fifth day the four sectors of the inner structure No. 1, have almost disap peared. No. 3 has disappeared entirely, and No. 2, which is almost the only polar- izing structure, exhibits a more intense white of the first order than appeared in any part of the lens. The ring No. 2 divides the radius of the lens equally. On the sixth day the structure No. 2 was still bright and uniform, but the polar- ized light had disappeared from every other part of the lens. On the seventh day the lens, which was always placed in water, burst its capsule, and there was no longer any trace of distinct polarizing structures. My next observations were made on the lenses of a cow nearly twenty years old. The following were the dimensions of the eye and the lenses. Inch. Diameter of eyeball .......... L66 Chord of the cornea (largest) T30 Chord of the cornea (shortest) ...... 1 -02 Longest diameter of lens ........ 0"827 Shortest diameter of lens 0'793 Thickness of lens . 0‘50 * Upon referring to my earlier observations, I find that in both the lenses of an ox there was only one struc- ture which was a positive one, and which had not yet divided itself into two structures, as in that of the cow under consideration. There was the appearance of a black space near the margin of the lens, but the polar- ized light both within and without that black ring was positive. In the lens of another ox, and of a bull, I found the positive structure separated into two positive structures by a distinct black ring, while an external negative structure was clearly developed. MDCCOXXXVH;. ttaUW. ^ JJicusvrcs, trlJv OF THE CRYSTALLINE LENS AFTER DEATH. 255 Both the lenses of the cow exhibited when taken out of the eye four beautiful struc- tures, in which the positive and negative structures alternate. The first and fourth were very faint, being the palest white of the first order. The third was also faint, but the second was both bright and large, and its tint was a brilliant yellow of the first order. After lying four days in water the lenses swelled so much that their dimen- sions were as follows : Inch. Diameter of one lens .......... 0-80/ Diameter of the other ......... 0*793 Thickness of the first .......... 0*647 Thickness of the second ....*.... 0*620 The lenses were still transparent, and the tint of the structure No. 2 had risen to an orange red of the first order. Having experienced great difficulty in the course of the preceding experiments in preserving the capsule of the lens transparent for several days, I made trial of various fluids, but found distilled water more suited to my purpose than any other. I there- fore began a regular course of observations on the crystalline lens of the sheep when placed in distilled water, which have afforded me very satisfactory results. The lens of a sheep a year and a quarter old, when newly taken out of the eye, ex- hibited in the distinctest manner only one structure, with slight traces of an external one. This structure was positive , and occupied almost the whole of the lens, as shown in fig. 3. The traces of an external structure, when carefully examined, showed it to be negative. On the following day this lens burst in the direction of the three septa. In the lenses of another sheep I found two structures like the preceding, but with this difference, that the external negative structure was more developed, as in fig. 4. On the following day this negative structure had extended itself inwards, but in con- sequence of an accident the lenses burst their capsule. In the lenses of another Cheviot sheep, where the external negative structure had just begun to appear, the wide positive structure shown in fig. 3 had just begun to separate itself by a dark neutral line, which was seen only in one of its four sectors, and which divided that sector into two. In another Cheviot sheep the principal positive structure had distinctly divided itself into two positive structures, separated by a dark neutral ring, as shown in fig*. 5. The same appearance was shown in the other lens ; and I have found it a very com- mon structure in the lenses of sheep at that age when they are killed for the table. When this division of the principal structure takes place the central one is at first faint, and the other a bright white of the first order, as in fig. 4. It becomes, how- ever, brighter and brighter till it nearly rivals the other in the intensity of its polar- ized tint, as in fig. 5, when another change begins to show itself. This change, similar to that which I have described in the lens of the cow, arises from the absorption of distilled water by the capsule of the lens. It first shows itself 256 SIR DAVID BREWSTER ON THE CHANGES IN THE STRUCTURE by the appearance of a brown tint in the dark neutral ring which separated the two positive structures. In the middle of the brownish black ring a trace of faint blueish light appears, generally in one of the sectors only, but gradually extends itself into a blue ring, which has negative double refraction and which is separated by distinctly formed black rings from the two positive structures, between which it lies. This state of the polarizing structure is shown in fig. 6, which is nearly the same as in the lens of the cow. The structure No. 1, beginning at the centre, was pretty bright, but No. 3 was much more so, and No. 4 very faint, though perfectly distinct. On the second day the blue ring No. 2 was much enlarged, and had encroached greatly on the brightest structure No. 3, having reduced it both in breadth and in- tensity. No. 4 has also extended itself at the expense of No. 3. On the third day the new structure No. 2 had become the brightest of all. No. 4 had increased also, whilst No. 1 had become smaller and fainter, and No. 3 was wholly obliterated. In another pair of lenses one of them burst at this stage of the development of the polarizing structures, while in the other the effect was singularly fine. No. 3 was wdiolly, and No. 1 nearly obliterated ; while the two new structures, which had no existence at first, were the only ones that remained. The new negative structure No. 2 consisted of four beautiful blue sectors of polarized light ; but in consequence of the great absorption of distilled water, and the consequent distension of the lens, it soon burst. I have already remarked that only one case has occurred in the course of my ex- periments in which the central structure of the lenses of quadrupeds was negative, as in fishes. In this case, however, the centre of the lens had its structure affected by some change in the condition of the fibres at their union in the three septa, which were not only distinctly seen, but had the polarizing structure clearly related to them. The polarized light filled up each of the three angles of 120° which lay between the three septa, and the intensity of the light was a maximum close to the three septa. Hence it is evident that the central negative structure was the result of an induration of the lens related to the septa, and had obliterated the positive structure which would otherwise have existed there. In examining the lenses of the horse I have observed the progressive development of its three structures as the animal advanced in age, and the extinction of all of them but one when the age of the animal was great. In both the lenses of a young horse three years old I found only one positive structure. In both the lenses of a horse whose age was unknown, I observed three structures beautifully developed. The central ones, which were extremely distinct and more beau- tiful in form and more intensely luminous than in any other quadruped which I had examined, were positive, the next structure negative, and the external on e positive. OF THE CRYSTALLINE LENS AFTER DEATH. 257 In the lens of another horse, whose age was also unknown to me, the remains of three structures were visible ; but the two positive ones, namely, the central and ex- ternal structures, had just disappeared, but were not encroached upon by the inter- mediate negative one. They were therefore black when seen by polarized light, as shown in fig. 7, while the remaining negative one was of the most brilliant yellow colour. In the lenses of a third horse, probably of an intermediate age, I found a structure intermediate between that of the two preceding ones. The following were the di- mensions of its lenses. First Lens. Second Lens, inch. inch. Longest diameter .... . 0*827 0*820 Shortest diameter 0793 0 793 Thickness Not measured 0*500 The first lens having been carefully prepared and immersed in distilled water, ex- hibited the beautiful optical figure which is but imperfectly represented in fig. 8. The central sectors were positive, but faintly illuminated. The wide and brilliant yellow and white structure was negative, and the external structure, which had just begun to appear, was positive. On the second day the black mass round the central sectors had enlarged itself, and become very black, having the form of a square lozenge. The yellow ring has risen in its tint to a brilliant pink yellow at the edges, the white ring within it having increased in width, and the white ring without it having diminished. On the third day the diameter of the lens had increased to 0*86 in all directions, and its thickness from 0*50 to 0*717 of an inch. The coloured ring has not changed greatly. On the fourth day the bright pink of the negative structure has risen to a bright blue, the pink and yellow being seen at its margin ; and the external positive struc- ture seems to be now conjoined with the blue negative structure, in consequence, no doubt, of the extension of the latter to the margin of the lens. The thickness of the lens was now upwards of 0*86, and the capsule came off', in consequence of which two of the blue sectors have become of a pale pink colour. The instant the capsule came off the lens shrunk in all its dimensions nearly the tenth of an inch. The second lens on the third day gave exactly the optical figure shown in fig. 8, having been newly placed in distilled water ; but the external ring seems to be slightly negative, like the yellow one. Its appearance was greyish and indistinct. On the fourth day the yellow ring had risen to a pale pink of the first order, and the outer ring was negative, as on the preceding day. On th e fifth day the pink ring had increased in intensity, and the other structures remained the same as before. On the sixth day the pink had risen to a very bright blue. The diameter of the 258 SIR DAVID BREWSTER ON THE CRYSTALLINE LENS. lens was now 0‘867 of an inch, and its thickness 0°733, being an increase of 0‘233 of an inch in thickness. On the seventh clay the capsule burst, and upon removing it and the soft pulp which formed about one tenth of an inch of the outer margin of the lens, the pink ring, with the white band both within and without it, and the black mass at the centre of the rectangular cross, were as distinct as ever. Hence it is manifest that the rise of the tint from yellow was not the effect of any expansive pressure produced by the swelling of the lens and the reaction of the capsule. The descent of the tint from bright blue to pink was no doubt owing to the po- larizing action of the extended capsule being withdrawn. In order to prove this I took the capsule, which is a tough and elastic membrane, and having stretched it, I found that it polarized, just before it tore, a white of the first order. Now the value of this tint is nearly equal to the difference between the values of the pink and blue of the second order of colours. The preceding results throw much light on the physiology of the crystalline lens ; and I shall have occasion, in a separate paper, to point out the conclusions to which they lead respecting the cause and cure of cataract. Allei'ly by Melrose , May 6th , 1837- [ 259 ] XVII. On the Temperature of Insects, and its connexion with the Functions of Respi- ration and Circulation in this Class of Invertebrated Animals. By George Newport, Esq., Member of the Royal College of Surgeons, and of the Entomo- logical Society of London. Communicated by P. M. Roget, M.D. Sec. R.S. Received June 5, — Read June 15, 1837. Every naturalist is aware that many species of insects, particularly of hymeno- pterous insects, which live in society, maintain a degree of heat in their dwellings con- siderably above that of the external atmosphere, but no one, I believe, has hitherto demonstrated the interesting facts that every individual insect when in a state of activity maintains a separate temperature of body considerably above that of the sur- rounding atmosphere, or medium in which it is living, and that the amount of tempe- rature varies in different species of insects, and in the different states of those species. Previously, therefore, to considering the connection which subsists between the evo- lution of animal heat and the functions of respiration and circulation in insects, I shall endeavour to prove that every species maintains a distinct temperature of body, the amount of which differs in the different states of the insect. I was first led to the particular consideration of the subject of temperature in in- sects by some observations on the temperature of wild bees in their natural haunts, which were made by myself at Richborough, near Sandwich in Kent, in the autumn of 1832, at the suggestion of Dr. Marshall PIall, for the purpose, — similar to that of my observations on respiration, as noticed on a former occasion*, — of ascertaining what relation, if any, subsists between the natural heat of these insects in their hyber- nating condition and the irritability of their muscular fibre. The results of these observations on the temperature of Bees are shown on Table III., Nos. 1 to 14, and together with many other facts connected with the physiology of insects were communicated to Dr. Hall a short time afterwards ■f-. These observations were * Philosophical Transactions, Part II. 1836, p. 551. t In submitting these observations on the Temperature of Insects to the consideration of the Royal Society, I have felt myself imperatively called upon to make the above remark, in explanation of the nature of my sup- posed obligations to Dr. Marshall Hall, -with regard to this and other subjects connected with the Physio- logy of Insects, in consequence of certain misrepresentations which were made on a recent occasion respecting my communications with that gentleman ; and I beg further to state, that many of the views here advanced respecting the temperature of insects, and also most of the subjoined Tables, particularly those on the tempera- ture of the Hive Bee, from the commencement of my observations to the month of May 1836, were commu- nicated by myself to Dr. Marshall Hall, at his own particular request, in the beginning of July 1S36, in the presence of my intelligent friend, and late pupil, Mr. John Osborn, who assisted me in making the observa- tions, and unto whom I am indebted for much valuable assistance during my investigations. MDCCCXXXVII. 2 M 260 MR. NEWPORT ON THE TEMPERATURE OF INSECTS. made in the usual manner, by placing a considerable number of insects of the same species together, and then introducing the thermometer among them. But it was a few days previously to making these observations that I first noticed the interesting fact, that each individual insect maintains its own temperature, which is perceptible externally by the thermometer, and that the amount of this varies in the different conditions of the same insect. The observation was first made on the larva of Sphinx Atropos, Linn., and on that of Pygcera bucephala, Steph., as will presently be shown. During the time I have been engaged in preparing the present communication I have become acquainted, through the kindness of Dr. Forbes of Chichester, with the recently published views of Dr. Berthold, of Gottingen, who has made a series of observations on the temperature of cold-blooded animals*, and among them several on insects, somewhat similar to those which I now have the honour of submitting to the Society. But excellent as are the views of that gentleman, he does not appear to have paid sufficient attention to the conditions of activity or rest in the insects at the time of making his experiments, and consequently has omitted to observe the important fact of the existence of a distinct temperature of body in individual in- sects-f-, and also those circumstances which augment or lessen its amount, and has estimated the temperature by placing many individuals together, which, as will pre- sently be seen, is open to several objections. Dr. Berthold has, however, anticipated me in the expression of one opinion, unto which we have mutually been led by our ob- servations, viz. that at all events the higher classes of invertebrated animals ought not to be considered as cold-blooded, since it is found that under certain conditions they have a temperature of body higher than that of the surrounding medium. Hausmann £ made an observation as long ago as the year 1803, which ought to have led to a proper understanding of the nature of the temperature of insects. He placed a perfect spe- cimen of Sphinx Convulvuli, Linn, in a small glass phial when the temperature of the atmosphere was 1 7° Reaum. (70°'25 Fahr.), together with a small thermometer, and at the expiration of half an hour the temperature of the phial was 19° Reaum. (74 °'7fi Fahr.), but soon afterwards he found that the temperature of the phial had sunk again to the previous standard 17° Reaum. He then repeated the observation with six spe- cimens of Carabus hortensis, Linn, with similar results. From what will subsequently be shown respecting the temperature of Carabi, which do not develop so large a quantity of heat, it is very probable, as suggested by Dr. Berthold §, that the results obtained by Hausmann arose from the bottle which contained the insects being touched by the hand of the operator. Dr. Berthold has observed this in his experiments, and I have constantly remarked the same thing myself when proper care was not * New Experiments on the Temperature of Cold-Blooded Animals, by A. H. Berthold, M.D., Gottingen, 1835. f Ibid. p. 36. Experiment 59. X De Animalium exsanguinum Respiratione. Gotting. 1803. p. 68. § Neue Versuche, &c., p. 11. MR. NEWPORT ON THE TEMPERATURE OF INSECTS. 261 taken to guard against its occurrence. Rengger* observed a distinct temperature in Melolonthce when many of them were collected together in an earthen vessel, but could not detect a distinct temperature in water-insects, or in Caterpillars. JucH-f~ likewise made observations on the temperature of the bee-hive, the ant-hill, and on the common Blister-flies. In a vessel containing a large quantity of the latter in sects, the Lyttce , he found the thermometer rise several degrees above the tempe- rature of the atmosphere. Br. Davy, according to Berthold^:, in making observa- tions on several species of insects, Scarabceus pilularis, Lampyris , Blatta, Gryllus , and Apis, found only a slight difference, except in the Gryllus, in which the difference amounted to five or six degrees, while in the Scorpion and Centipede he found a temperature lower than that of the atmosphere. Dr. Burmeister, in his Manual, recently translated by Mr. Shuckard, has spoken of the temperature of insects, but only of insects in society, and has referred to the observations of Juch, Reaumur, &c., and although he believes in the existence of individual temperature in insects, has given no observation of his own to prove the fact, while Dr. Berthold, in the work just noticed, (experiment 59,) made on a single insect, could not detect it, nor could he do so in every species when the observation was made on a number of indi- viduals collected together. It is evident, therefore, that although the existence of individual temperature is inferred from experiments on insects collected together, it yet remains to be proved that every individual insect in a state of activity invariably maintains a certain amount of temperature, which is readily appreciable by the in- struments we are enabled to employ. Before detailing the results of my observations it is necessary to explain the manner in which the observations themselves have been made, and to point out those circum- stances which seem to have been overlooked by other inquirers in their experiments on the temperature of insects. It is only by a careful attention to those circum- stances that we are enabled to detect the existence of temperature in single insects, and to understand the causes of its variations at different periods. The thermometers employed by me on every occasion are of the smallest possible calibre, with cylindrical bulbs about half an inch in length, and scarcely larger than crow-quills, and are similar to those employed by Professor Daniel for the purpose of ascertaining the dew point. They were made by Mr. Newman of Regent Street, and are graduated from zero, or from a few degrees below freezing to about 1 10° or 120°. Whenever great delicacy of observation is required, in order to observe the varying temperature of an insect during a state of partial rest, it is necessary to use the same instrument for ascertaining the temperature of the atmosphere as for that of the in- sect, otherwise a great difficulty will arise, from the well known circumstance that two thermometers, be they ever so delicately constructed, and carefully compared * Physiologische Untersuchungen iiber die thierische Haushaltung der Insecten. Tubingen, 1817, p. 39. t Ideen zu einer Zoochemie, Bd. 1. 1800, p. 92. + Neue Versucbe, &c. p. 12, 13. 2 M 2 262 MR. NEWPORT ON THE TEMPERATURE OF INSECTS. with each other, will seldom if ever both indicate precisely the same amount of tem- perature in exactly the same space of time. The mode of taking1 the temperature is either by allowing the insect to remain with the soft ventral surface of its abdomen pressing against the bulb of the thermometer when in a state of rest, or by pressing the thermometer firmly against its body when in a state of excitement, the insect being held during the time between a pair of forceps covered with woollen, in order that the contact of the fingers of the operator may not interfere with the correctness of the observation by unnaturally increasing the temperature of the insect. It is also further necessary to guard the hand with a glove, or non-conducting substance, to prevent the thermometer itself from becoming affected by it during the experiment. Much caution also is necessary when the same thermometer is employed to ascertain the temperature both of the atmosphere and of the excited insect, to guard against one very material source of error. It is necessary first to ascertain the temperature of the atmosphere, and then that of the insect, because if this be not attended to, and the experiment be made by taking the temperature of the insect before observing that of the atmosphere, the moisture on the bulb of the instrument occasioned by the con- densation of the cutaneous perspiration from the body of the animal will occasion during its drying or evaporation, while taking the temperature of the atmosphere, an indication of a lower amount of atmospheric temperature than what really exists, and consequently the apparent difference between the temperature! of the insect, pre- viously taken, and that of the atmosphere, will be much too great, and thereby appear to indicate a higher temperature than what the body of the insect really possesses. When the temperature is taken during a state of rest, the thermometer is placed beneath, and as completely covered by the abdomen of the insect as possible, while a second thermometer, which has been very carefully compared with the first, is placed on the same level with and at a short distance from it to indicate the tem- perature of the atmosphere. When the temperature of active volant insects is to be taken, it is preferable to inclose them singly in a small phial, introducing them with the forceps as before, and being particularly careful not to touch the phial with the fingers. The degree of activity or quiescence of the insect must always be parti- cularly noticed, and also the number of inspirations. By attending to these facts we acquire a knowledge of the amount of respiration compared with the quantity of heat evolved, as indicated by the thermometer. The temperature of the insect taken on the exterior of the body is always a little lower than that of the interior ; but the difference is not so great as might at first be imagined, so that I have generally pre- ferred taking the exterior temperature, because the observations are then less com- plicated by unnatural causes. The interior temperature is seldom if ever more than a degree and a half, or at most two degrees above the exterior, and often not even half a degree, when the insect is in a state of perfect rest. Perhaps it may be urged as an objection, that when the bulb of the thermometer is applied to the exterior of the body, it can seldom be so completely covered as to indicate the whole amount of MR. NEWPORT ON THE TEMPERATURE OF INSECTS. 263 heat developed. But this objection, although at first plausible, must be considered valid only when the observations are made very quickly. But even were the objec- tion substantiated it would be of but little consequence, because it is only the relative amount of heat developed by one insect as compared with that of another, when the observations on both are conducted in a similar manner, which is ultimately sought for, it being almost impossible to ascertain the exact amount evolved by any single insect. It may also be urged as an objection to this mode of taking the temperature of insects in a state of excitement, that when an insect is respiring very rapidly, the friction of the segments of its body against the bulb of the thermometer may evolve a certain amount of heat independent of the natural heat of the insect, and thereby indicate a higher temperature in the insect than that which really exists. In order to meet this objection, I made a number of trials with my thermometers, by using, as nearly as could be ascertained, about the same amount of attrition against the bulb of the instruments as that which is exerted by the segments of the excited insect during its laboured respiration and efforts to escape, and found that so small a quantity of heat is evolved that it is not in the slightest degree indicated on the scale of the thermometer. Hence I have not in general found it necessary to take the tem- perature of the interior of the body, although I have done so in a few instances, be- cause there are also other circumstances which interfere with the correctness of the observation. The first of these is the large size of the instrument employed compared with that of the body of the insect into which it is inserted, and the consequent ne- cessary loss of a certain amount of caloric, which becomes latent in the thermometer, before there is any indication of increased temperature on the scale, and because also of the unavoidable escape of a large amount of caloric into the surrounding atmo- sphere, and because still further it is only at the very instant after the introduction of the thermometer into the body of the insect that the real perceptible amount of tem- perature is indicated, while the insect under observation is every moment losing the power of generating and of maintaining its temperature, owing to the injury that has been inflicted upon it. These objections do not occur when the observations are made on the exterior of the insect, which from its being uninjured, continues to possess its power of generating heat unaffected by those circumstances which tend very mate- rially to interfere with or destroy it, while a sufficient length of time is afforded for the production of its full amount of heat after a certain quantity has become latent in the thermometer, before the observation of the amount is taken. These are the principal circumstances to be attended to in ascertaining the tem- perature of insects, and which have directed me in my observations. 264 MR. NEWPORT ON THE TEMPERATURE OF INSECTS, I. Temperature of the different States of Insects. 1 . The Larva. The temperature of the larva is always lower than that of the perfect insect of the same species, provided both individuals be in a similar state of activity relative to their usual condition. This circumstance must never be neglected when making comparative observations on the different states of the same insect. Thus the larva of the more perfect hyinenopterous insects, the common Humble Bees, Bomhi, An- thophores, Eucerce, &c., which in all their stages have a temperature higher than perhaps any other insects, in their active larva state vary from about 2° to 4° Fahr. above the temperature of the surrounding medium, while the same individuals in their perfect state, when moderately active, have a temperature of from 3° to 8° or 10° Fahr. higher than that medium ; but when the same insect is very greatly excited the amount of difference is raised to a much greater extent. There is a similar difference between the temperature of the larva of the common Flesh Fly, Musca vomitoria, Linn. and that of its perfect insect, only that the amount is not so great as in the hyme- nopterous insects. In the Musca the amount of temperature in the larva state seldom exceeds la5, and in the perfect perhaps not more than 2°*5, above that of the sur- rounding medium. It is probable that this estimate of the difference between the larva and perfect state of dipterous insects may be rather too little, owing to the difficulty of making observations on these insects individually, their small size ren- dering precision in the experiment almost impossible. But the fact is sufficiently clear that they have not so high a temperature as hyinenopterous insects. The same difficulty does not exist in making observations on large insects, particularly on the large soft-bodied larvae of the Sphinges, and accordingly it is found that in these lepi- dopterous insects we are better enabled to ascertain the maximum amount of heat evolved by the larva, and the difference which exists between its powers of generating heat and that of its perfect insect. This difference is greater in lepidopterous insects than in dipterous, and approaches nearer to the hyinenopterous. It was in the larvae of lepidopterous insects that I first observed the existence, and the varying amount of temperature in individual insects. These observations were commenced in Sep- tember 1832. At 24 p.m. September 14, the temperature of the atmosphere being 62°5 Fahr., the bulb of a thermometer was applied to the under surface of the body of a full-grown larva of Sphinx Atropos , Linn., which had discontinued feeding pre- paratory to undergoing its transformation. The insect then weighed 365|- grains. Previously to the observation it had been for a considerable time in a state of violent excitement, and was moving about with great rapidity. Its temperature, as indi- cated by the thermometer, was then 70° Fahr., or 7°’5 higher than that of the atmo- sphere. This, however, was much higher than its real temperature, which is probably not more than 3°, and was occasioned, as I subsequently had reason to believe, by MR. NEWPORT ON THE TEMPERATURE OF INSECTS. 265 holding the insect in my hand while making the observation. At 12^ midnight, at- mosphere 60o,5, the larva perfectly at rest had a temperature of only 61° Fahr. ; and at 7 o’clock on the following morning, September 15, having remained perfectly quiet and apparently asleep since the last observation, the temperature of the atmosphere continuing at 60o-5 Fahr., when the bulb of the thermometer was gently pressed against its side without disturbing it, and allowed to remain there for a quarter of an hour, the mercury was not perceptibly affected, the temperature of the larva, now in a complete state of rest, being exactly that of the surrounding atmosphere. Ob- servations in every respect similar to these were also made at the same time on the larva of the Bull-headed Moth, Pygcera bucephala , Steph. At midnight the tem- perature of the atmosphere, as before stated, being 60o,5, the thermometer was ap- plied to the under surface of a larva that had been lying perfectly at rest for several hours, and although it now became slightly aroused its temperature was only 61° Fahr. At 7 on the morning of the 15th, the larva still perfectly quiet, and the thermometer placed in contact with it, and, as with the Sphinx Atropos, allowed to remain for a quarter of an hour, there was no indication of any increase of temperature, the tem- perature of the insect being exactly that of the atmosphere ; but a few hours after- wards, when the thermometer was again applied to the same insect, which had be- come slightly active, the mercury rose to 60°*5, the temperature of the atmosphere being then 60° Fahr. At 6^ on the morning of the 17th the observations on this species were repeated. The temperature of the atmosphere was then 62° Fahr. ; and when the bulb of the thermometer was applied to a full-grown larva, which had been remaining several hours at rest, the mercury rose very nearly to 63° Fahr. The ob- servation was then repeated on several other individuals of the same species, which had been lying at rest, and with precisely similar results. The bulb of the thermo- meter was then placed in a box which was filled with these larvae, and being com- pletely covered with them was suffered to remain for ten minutes, during which time they were in a state of great activity, and the mercury rose to 63°’3 Fahr., a differ- ence of 1°*3 Fahr. Subsequent observations on the temperature of other species of lepidopterous insects confirmed these observations ; and it was remarkable that the amount of temperature in the larvae of different tribes of this order is pretty nearly the same. On the 26th of June 1834 I examined the full-grown larva of Pavonia minor , which like the preceding species had been at rest for several hours, and found that the temperature of the atmosphere being 68°, the temperature of the insect was only 680,3. The insect then became a little excited, and the mercury rose to 680,7 ; and when still further excited to 680,9, and ultimately to 69°‘3, being a difference of 10,3 above that of the atmosphere, thus proving that the temperature of an insect in- creases immediately it becomes active, and that the increase is in proportion to the degree of activity, and probably also to the quantity of respiration of the insect. From these facts it is sufficiently clear that individual insects possess a temperature of body above that of the surrounding medium, and that the amount is not constant 266 MR. NEWPORT ON THE TEMPERATURE OF INSECTS. in the same insect, but varies according to certain conditions of the insect. These views were still further confirmed and extended by observations on the Sphinx li- gustri, S. populi, S. ocellata , Linn., and Cerura vinula, Steph. The first and last of these insects, from their large size and frequency of occurrence, afford us the means of ascertaining all the facts connected with the temperature of larvae, and are those on which most of my subsequent observations have been made. It is at about the fifth or sixth day after the larva of Sphinx Ugustri has assumed its last skin, that it evolves the greatest quantity of heat. It then feeds most voraciously, and usually weighs about 80 grains. Its greatest temperature is then 1°*3 above the temperature of the atmosphere. I have seldom or ever found it higher, while on the eighth or ninth day it seldom exceeds nine tenths, and a little while before its change into the pupa state perhaps not more than five tenths. Its quantity of respiration at that time is diminished, and its temperature is reduced by copious cutaneous perspiration, which becomes very apparent when the insect is much excited. The difference which exists in the maximum amount of heat generated by the larvse of different species of the same class of insects, appears to have some reference to the habits of those species. The greatest amount, so far as I have yet ascertained, excepting only the Sphinx Airopos before noticed, appears to be generated by the larva of the Puss Moth, Cerura vinula, Steph., which usually lives on the boughs of trees, and subsequently undergoes its changes on the trunk or limbs of the tree a few feet from the ground, has a higher temperature of body, and a quicker circulation of its fluids than the larva of the Sphinx, which undergoes its changes in the earth. The larva of the Cerura in its most active condition sometimes has a temperature of l0, 8, or nearly half a degree higher than the Sphinx ; but I have not observed the same difference between the temperatures of the perfect insects of these species, both of which constantly reside in the open air. The amount of difference between the perfect insect and larva in these species, like that of the hyinenopterous insects, is very great. A perfectly healthy specimen of Sphinx Ugustri in its perfect condition after violent exertion, has sometimes a temperature of nearly 8° above that of its larva. The usual difference is about 5°, and the same is the case with the Cerura. When the internal temperature of a larva of the Sphinx or Cerura is taken, it is found to vary from • 5 of a degree to 1° above that of the external. But all observa- tions on the internal temperature of larvse, more particularly of soft-bodied larvse, are necessarily uncertain, on account of the reasons before stated. Still it is some- times desirable to ascertain its amount, particularly when the specimens have been kept in a steady medium. When the internal temperature of the larva of Anthophora retusa, Steph. is taken with the necessary care, it is found to be nearly or quite a degree above that of the exterior ; but the difficulty in making correct observations on these larvse is exceedingly great, owing to the rapidity with which they part with their natural heat when exposed to a varying medium. Hence when the observations are attempted to be made, even with regard to external temperature, in the natural MR. NEWPORT ON THE TEMPERATURE OF INSECTS. 267 haunts of these insects, they seldom afford very satisfactory results. In order there- fore to ascertain the real temperature of these larvse I collected a number of separate nidi, each of which inclosed a larva, and placed them for a few days in a room, the temperature of which varied but very slightly. Each larva was then submitted to observation immediately it was removed from its cell. The temperature of the room in which the nidi were kept was 57° Fahr. The first specimen examined had been lying partly exposed for a short time, and the larva perhaps had thereby had its tem- perature diminished. When the bulb of the thermometer was inserted into its ab- domen the mercury rose only to 57°'8, while its external temperature was scarcely above that of the atmosphere. The second specimen had been better preserved from exposure, but the mercury rose again only to 57°'8. In a third, and apparently very healthy specimen, it rose to 58°. In a fourth, in every respect healthy, to 60° for about a moment, but rapidly sunk again to a little more than 59° ; in a fifth it rose also to 60° ; in a sixth to 590,5 ; and in a seventh and eighth to 60°. On another oc- casion, when the medium in which the larvae were kept was 57°’3, the temperature of the under surface of a larva was 60°, but when the bulb of a thermometer was care- fully passed into its abdomen the mercury rose to 61° Fahr. In the larvae of Musca vomitoria, Linn., treated in a similar manner, the temperature of the atmosphere being then 560,8, the mercury rose to 57°'S, but was maintained at that height only for a few seconds, owing to causes before noticed. I have not yet had an opportunity of examining the larvae of coleopterous insects, which judging from their similarity to those of the hymenopterous and dipterous classes, it is fair to infer evolve a similar amount of heat. Neither have I been able to examine the orthopterous and hemipterous larvae, which, from their approaching very near to the condition of the perfect insect, probably differ but little in their pro- duction of heat and the quantity of respiration. 2. The Pupa. The pupa state being in all insects which undergo a complete metamorphosis a condition of absolute rest, the temperature of the individual is in general lower than at any previous or subsequent period of its existence, and is only equal to, or at most but very little above that of the surrounding medium. But in those insects which do not undergo a complete metamorphosis, the temperature probably is intermediate between that of the larva and perfect condition. In those species the individuals continue active during their whole life. These exceptions include most of the hemipterous, orthopterous, and a few coleopterous insects, and cannot properly be included under the designation of pupa, the term being here intended to apply strictly to the lepi- dopterous, dipterous, hymenopterous, and a few coleopterous insects. The only periods during which the temperature of a pupa is higher than that of the surrounding medium, are, first at the period of, or within a short time after its change from the larva state, while it is still active, and respiring very freely, and be- mdcccxxxvii. 2 N 268 MR. NEWPORT ON THE TEMPERATURE OF INSECTS. fore it has completely subsided into a state of rest. At that time, when the whole of its energies are called into activity in effecting its transformation, the temperature of the pupa may be considerably higher than that of the surrounding medium. Thus I have found it in the Sphinx, immediately after changing, equal to that of the active larva. When the temperature of its cell in the earth was 68°'3, the temperature of the newly-changed pupa within it was 69°-5, a difference of 10,2 ; but within a single hour afterwards, while the body of the pupa was yet soft, the difference was scarcely more than three tenths of a degree. So likewise when a pupa is very much disturbed for the purpose of experiment, its temperature becomes considerably increased. Also when the medium in which the pupa is living is suddenly diminished, or when the pupa is removed from a warmer to a colder medium; and lastly, when the pupa, aroused by the stimulus of gradually increasing external temperature, begins again to respire freely, during a short time before it is developed into the perfect insect. In each of these cases its temperature may be more or less high, according, in the first place, to the rapidity with which the temperature of the surrounding medium has been diminished, and in the second according to its quantity of respiration in a given time. The increased temperature of a lepidopterous pupa arising, as it appears to do, with increased respiration, is coincident with the power which the insect gra- dually acquires before it is able to fissure its prison-house and liberate itself from the puparium ; while the hymenopterous insect, which lives in society, and remains during its nymph or pupa state inclosed in an almost impervious cocoon, has its tempera- ture artificially increased by the incubation of insects already developed. It is very shortly after an insect has entered the pupa state that its respiration is diminished, and its temperature sinks down very nearly to that of the surrounding medium. At 8 a.m., November 10, two pique of Sphinx ligustri, which had remained during several weeks with other specimens entirely undisturbed, were carefully re- moved with the forceps into glass-stoppered phials, the temperature of which was exactly that of the room in which the pupa had previously been kept. They were examined during three succeeding days, the temperature of the atmosphere being also very carefully noted. The temperature of the phials varied a little, but there was not the slightest difference between the temperature of the atmosphere of the phials and of their respective pupse, even when the thermometer was allowed to remain in con- tact with the pupse for several minutes. The variations in the temperature of the phials are shown in the following Table. Table I. Temperature of Pupse. Period of observation. Atmosphere. Phials. Diff. Remarks. Nov. 10, 1834. A.M. 8 o 53-4 No. 1. 53-4 f No. 2. 53-4 r.M. 1£ 54-5 No. 1. 54-7 •2 Pupa had been a little excited. f No. 2. 54-5 11 r.M. 1 51-5 No. 1. 51-6 •1 Atmospheric temperature sinking. s No. 2. 51-6 •1 12 A.M. 9 51-9 No. 1. 51-8 Atmospheric temperature rising. No. 2. 51-9 13 A.M. 9$ 50-9 No. 1. 51 •1 Atmospheric temperature sinking. 1 No. 2. 51-1 •2 MR. NEWPORT ON THE TEMPERATURE OF INSECTS. 269 From these observations it is seen that when the pupa was disturbed there was a slight evolution of heat ; the amount of this was greatest when the temperature of the atmosphere was subsiding. But as it appears reasonable to infer, a priori , that the internal temperature of the pupa may be higher than that of the surrounding atmosphere, although the thermometer be not perceptibly affected when applied to the thick exterior of the puparium, another specimen of the same insect was subjected to examination. This specimen had been lying for several weeks on the surface of the ground, in the shade, exposed to all the variations of the atmosphere. During that period the temperature of the air had seldom been more than a few degrees above freezing, while on the three nights immediately preceding the making of this observation, on the morning of the 23rd of March, the temperature of the atmosphere bad ranged from 2° to 4° Fahr. below 32° Fahr. On the night of the 22nd it was from 3° to 4° below that standard. Under these circumstances there appeared to be a favourable opportunity of ascertaining the real internal temperature of the pupa. Accordingly at a.m., atmosphere perfectly calm, and its temperature 320-6 Fahr., and gradually but very slowly rising, an incision was made quickly with a pair of scissors through the posterior part of the pupa, which was held for the moment between a pair of forceps that had previously been cooled down to the temperature of the atmosphere. The fluids of the insect instantly gushed out, and the entire cy- lindrical bulb of a small thermometer was immediately passed into the body of the pupa. It was the same thermometer which only a moment before had been used to ascertain the temperature of the atmosphere. The mercury in the scale immediately sunk to 320,3 Fahr., or three tenths below that of the atmosphere, and it was main- tained at that standard for fifteen minutes, while the temperature of the atmosphere was still slowly rising. At the expiration of that time the pupa was slightly com- pressed with the forceps, and its temperature rose slowly to 320,7, that of the atmo- sphere being 320,8. In this observation there was not the objection of part of the bulb of the thermometer being exposed, nor of evaporation taking place from the surface of the wetted bulb. Hence it is fair to conclude that the internal tempera- ture of a pupa, perfectly at rest, is scarcely above that of the surrounding medium, when the temperature of that medium is stationary. We have still further evidence that this is really the case, when instead of a single specimen a considerable number of pupae are employed. When the bulb of a thermometer was completely covered with the pupae of the Flesh Fly, Musca vomitoria , Linn., the temperature of the atmo- sphere being 560,5 Fahr., the mercury was not in the slightest affected, but continued exactly at the same standard. But when the more delicate pupae, or nymphs, are employed, as those of Bees, the temperature of a number of them which have been somewhat disturbed is generally a little above that of the surrounding medium ; and this is also the case when a single specimen is employed, if its temperature be taken during the summer, when the nymph is active and preparing to pass into the perfect state, as shown in Table III., No. 39. But this difference very soon becomes reduced 2 n 2 270 MR. NEWPORT ON THE TEMPERATURE OF INSECTS. by the greater rapidity with which insects in the condition of nymphs part with their natural heat than even the larva ; and this apparently is the reason why most hyme- nopterous insects select those situations for their young which are found to be the worst conductors of heat. This evidently is why the Anthophora incloses its larvae in cells constructed in the vertical sections of banks of earth which are exposed to the morning sun, and why the Hive and Humble Bees crowd over those cells which are about to produce the perfect insect, when the inclosed nymphs are most in need of increased temperature to invigorate them for the change they are about to undergo. 3. The Imago, or Perfect State. When an insect has assumed its last or perfect condition it has a higher tempera- ture of body than at any other period of its life, and when in a state of activity is not so much influenced by sudden changes of atmospheric temperature as in its earlier states of existence as larva or pupa ; and it has also a greater power of generating as well as of maintaining its temperature. But it is not until some time after an insect has assumed its perfect form that it is able to support its full temperature. This period is longer or shorter, according to the habits of the species. When a lepido- pterous insect leave its puparium with its whole body soft and delicate, and its wings undeveloped and hanging uselessly like little buds from the sides of its thorax, it so rapidly parts with its temperature that it appears to have a lower degree of heat than at the time when it was about to pass from the larva to the pupa state, and it imme- diately seeks a retired situation, where it may suspend itself vertically at rest, and complete the development of what are now to become its most important organs of locomotion. In effecting this development it is well known that the insect first begins to breathe very deeply, and it continues to do so for a considerable time. The in- spired air passes from the large air-sacs in the abdomen of the insect into the base of the wings, with which the air-sacs have a direct communication* ; and while the ramified tracheae in the wings are becoming elongated and distended, and the wings in consequence developed, the temperature of the insect again begins to increase. But it is not until the wings have become firm and fitted for flight that the insect is enabled to generate its full amount of temperature. Thus in the Puss Moth, Centra vinula, Steph. half an hour after coming from the pupa the temperature of the insect was only "2 of a degree above that of the atmosphere ; at an hour afterwards -3 ; at an hour and a half -6. During this period the insect was only in a moderate state of activity. But at two hours and a half, and when a little more active, its temperature amounted to one degree and two tenths ; and on the following day, when perfectly strong and excited as during rapid flight, it amounted to nearly 7° above that of the atmosphere (Table V. Nos. 25 to 35.). This is exactly the same with the Sphinx ligustri, *Lii$N. An individual which had * Mr. Goadby, Medical Gazette, April 2, 1836. MR. NEWPORT ON THE TEMPERATURE OF INSECTS. 271 only left the pupa state about an hour and a quarter had a temperature of only *4 of a degree above the atmosphere; but at the expiration of two hours and a quarter, when it had become strong and had just taken its first flight, it had a temperature of 5°*2 (Table V. No. 7-) ; while another specimen, which had been longer exerting itself in rapid flight, had a temperature of 9° above that of the atmosphere (Table V. No. 12.). Now these very species in their larva state, as we have before seen, have not more than 1°*3 and l0-8 above that of the atmosphere. The circumstances con- nected with the power of generating heat are nearly the same in the development of hymenopterous as in lepidopterous insects, the only difference being that those hy- menopterous insects which live in society have their heat augmented artificially before leaving the cocoon or pupa case. But when the young bee comes forth it parts with its temperature most rapidly, unless it be immediately protected by warmth af- forded to it by the bodies of other individuals. But when the same insect a few hours afterwards has become fully able to perform all the duties of its existence, it sometimes has a temperature of perhaps 20° Fahr. above that of the surrounding medium, while the temperature of its larva is scarcely more than 3° or 4° Fahr. During the whole of my observations I have not met with a single instance in which I was unable to detect a certain amount of external temperature in perfect insects in a state of activity, and it may therefore be regarded as proved that the whole class develop a certain amount of external heat. This uniformity of results, however, has not been observed in the experiments by Dr. Berthold *, before alluded to, and I can only attribute the discrepancy which exists between his observations and my own, to the circumstance of his omitting to attend particularly to the degree of activity or rest in the insects on which he experimented. I am the more inclined to attribute it to this omission, because in his 58th experiment, page 36, he says that in “ twenty chamber flies there was no development of heat or external temperature,” the observation being made in a steady atmospheric temperature of 17 Reaumur (70o,25 Fahr.). In my own observations upon insects of this order, as in an experi- ment with about the same number of specimens of Musca vomitoria, Linn, in their perfect state, the atmosphere being about 52° Fahr., the insects in a state of activity evolved from 1° to 1°’9 Fahr. of external heat, while in the same individuals in a state of partial rest the amount of heat did not exceed '6 of a degree. Again, in Dr. Ber- thold’s 59th experiment, which evidently was made in order to ascertain whether single insects evolve any appreciable heat, the bulb of a thermometer was passed into the body of a “ single chaffer,” through an opening under the wing-covers, and examined half-hourly for about two or three hours, but no heat was detected. In several experiments made by myself in a similar manner to this by Dr. Berthold, particularly on the Melolontha vulgaris, Steph. (Table VI. Nos. 45 to 52), the amount of heat developed varied from 2° to 9° above that of the atmosphere, and was always in proportion to the activity of the insect. * Neue Versuche, &c., p. 36. 272 MR. NEWPORT ON THE TEMPERATURE OF INSECTS. These facts are sufficient to prove that insects have a high temperature of body, and that it is higher in their perfect than in their larva or infant condition. They also beautifully accord with the facts ascertained, and the views deduced from them by Dr. Edwards, respecting the difference between the temperature of the young mammiferous animals and their perfect adults. II. Temperature of Insects as influenced by various conditions. Abstinence, Inactivity, Sleep, Hybernation and inordinate Excitement . 1. Abstinence . Having shown the difference between the temperature of the larva and perfect in- sect in a state of activity, we come next to the consideration of certain conditions under which the temperature both of the perfect insect and of the larva will some- times subside, almost to that of the surrounding medium. When an insect, whether it be in its earlier or later condition, has been long deprived of food, its power of ge- nerating and of maintaining its natural heat is diminished. But this diminution of power does not keep pace with the length of time it has been fasting, but is only in an inverse degree. In the larva of Sphinx ligustri, Table XII., and in Acrida viri- dissima, Table VI. Nos. 9 to 16, the amount of heat is much below the usual quantity evolved when the insect is not deprived of food, and in a state of activity. When the proper quantity of food is again supplied to these insects, their respiration is re- stored to its original condition, and they again evolve a full amount of heat. When a larva that has been deprived of food, or has been fed sparingly, is preparing for transformation, its natural temperature is reduced to within two or three tenths of a degree of that of the surrounding medium. This was the case with the larva of Cerura vinula, Steph. (Table X. No. 30, B.), which although actively employed spinning its cocoon, had, at one time, a temperature of only two tenths of a degree above that of the atmosphere; while the other specimen. No. 1 . A, which had been sup- plied with its full amount of food of proper quality, had a temperature under similar circumstances, and almost at the same hour, of *7 tenths above that of the atmosphere. In another larva of Sphinx ligustri, which having been inadequately supplied with food soon after it had assumed its last skin, and thereby retarded three or four days beyond the usual period before it began to prepare for transformation, the tempera- ture of its body, while in the state of the greatest muscular excitement in attempting to rupture and cast off its exuviae, was only ‘3 tenths of a degree above that of the atmosphere. 2. Inactivity . Another source of diminished temperature in insects is inactivity. In this condi- tion, as in a state of abstinence, the quantity of respiration is also diminished. When an insect becomes quiet, after having continued for some time in a state of moderate MR. NEWPORT ON THE TEMPERATURE OF INSECTS. 273 activity, its temperature gradually subsides, and continues to be diminished in pro- portion to the length of time it remains inactive, until it has approached very near to the temperature of the atmosphere. Thus many of those insects which have a com- paratively high temperature when in a state of active exertion in the early part of the summer, have their temperature greatly reduced when they become inactive at the end of autumn ; and when an insect passes from a state of inactivity into that of na- tural sleep, its temperature subsides even during summer, very nearly to that of the surrounding medium. This was the case with the larvse of Sphinx Atropos and Bomhyx hucephala, as shown in the observations on larvse. 3. Sleep . All insects enjoy a periodical state of repose, or natural sleep. They are endowed with this privilege of life for the renovation of their voluntary energies in common with other animals. It is at this period that the involuntary functions of the body, which, together with the voluntary, are exercised to their utmost amount during the willing activity of the individual, begin steadily to subside, in order to restore the equilibrium which ought to exist between the healthy capability of the organs em- ployed and the amount of energy expended. Respiration, circulation, digestion, and the evolution of animal heat are all diminished, until a fresh amount of voluntary power is again generated, and the animal is aroused to the enjoyment of it either by its superabundance, or through the agency of external stimuli. It is no small amount of this privilege that is enjoyed by insects. I have witnessed sleeping in almost every order of insects, and am satisfied that they enjoy as great a proportion of rest as any other animals. Many insects will remain in a state of rest during ten, twelve, or twenty hours at a time, even in their seasons of activity, influenced as they are by external stimuli. Every one is aware that the common May Chaffer, Me- lolontha vulgaris, will often continue sleeping on the leaves of the lime tree throughout the whole of a fine summer’s day, and not become active until near sunset. The case is the same with nearly the whole tribe of Sphinges and Moths, while many Butter- flies which are active during sunshine, will often remain for two or three days, when the weather is gloomy, affixed to the very same spot. The common Honey Bee, Apis mellifica, Linn., notwithstanding the bustle and activity of the hive, enjoys its share of repose as well as other insects, even amidst the apparent commotion of its own dwelling. Huber observed that his bees often inserted their heads and part of their bodies into the empty combs, and remained there for a considerable time. They were then quietly sleeping in the cells. At other times they appear to sleep for short intervals on the surface of the combs. I have seen them towards the latter end of summer sleeping in the cells in great numbers for many hours together. It is there also where many of them pass a portion of their winter, doubtless in a state of hyber- nation, or most profound sleep ; and it is an interesting fact, that this inactivity of the inhabitants of the hive during winter, is accompanied by a diminution of heat in 274 MR. NEWPORT ON THE TEMPERATURE OF INSECTS. their dwelling, as I shall presently have an opportunity of proving. The common Humble Bee, Bombus terrestris, even in the month of April, will continue in a state of rest# approaching to the condition of hybernation for at least twenty hours, while its temperature becomes diminished in proportion to the diminution of its quantity of respiration, which also is diminished in proportion to the length of time it remains in a state of rest. This is always the case with insects when the temperature of the surrounding atmosphere is stationary. But if the temperature of the atmosphere is gradually increasing when an insect is passing into a state of repose, the temperature of the insect will continue to rise also, accompanying that of the atmosphere, but not so rapidly as it would have done were the insect in a state of activity, so that the temperature of the air and of the insect will at length arrive at exactly the same level; and if, when this is the case, the temperature of the atmosphere continues rising, that of the insect will also accompany it for a certain time ; but if the increase of atmo- spheric temperature be very rapid, the temperature of the insect will at length be found to be one or two tenths of a degree below that of the atmosphere. When this has happened the insect generally becomes slightly aroused, fetches one or two deep inspirations, and its temperature very quickly rises to that of the atmosphere, while the insect relapses again into its previous slumber. On the other hand, if the tempe- rature of the atmosphere be gradually diminishing, that of the insect will also con- tinue to be diminished, but will remain for a longer period higher than that of the atmosphere when the atmosphere is rising, or is remaining stationary, since the in- sect during sleep can neither acquire nor part with its heat so rapidly as the atmo- sphere around it. But if the temperature of the atmosphere continues to subside rapidly, the temperature of the insect during the whole period of its most profound sleep may continue considerably higher than that of the surrounding medium. These facts may be readily demonstrated by careful observations on the smooth-bodied larvee of Lepidoptera, the best of which for this purpose are the larvae of the Sphinges, in which besides the varying amount of temperature, the correspondent rate of pul- sation may also be observed with great accuracy. The larva of Sphinx ligustri upon which the observations detailed in Table No. II. were made, had arrived at the seventh day of its age after assuming its last skin, or at about the thirtieth day after coming from the egg, and consequently was nearly full grown, and beginning to feed rather less voraciously than on the two preceding days. At the time my ob- servations were commenced it had been lying at rest about an hour, having fed plen- tifully in the morning. The whole period of observation, throughout which it was sleeping almost uninterruptedly, was about nine hours. During this period the thermometer was allowed to remain entirely undisturbed on a table in close contact with the ventral surface of the insect, while a second thermometer, with which the one employed to take the temperature of the insect had been carefully compared, was used to take the temperature of the atmosphere, which throughout the obser- * Philosophical Transactions, 1836, Part II., p. 555, Table L, No. 27. MR. NEWPORT ON THE TEMPERATURE OF INSECTS. 275 vations was perfectly calm. Thrice during this period of repose the insect became slightly aroused, and each time, as shown oil the Table, the number of its pulsations and its temperature slightly increased, but subsided again as the insect relapsed into its previous condition. Once also it was disturbed by the passing of excrement, im- mediately after which there was a slight increase of its temperature, and of the pul- sation of its dorsal vessel, and the insect continued awake for a few minutes, but having relapsed into its former sleep its temperature and pulsation again subsided. Table II. Exhibiting the diminished temperature of body during sleep, and also a coincident diminution in the rate of pulsation of the dorsal vessel in different conditions of the insect during the last three days of the larva state of the Sphinx Ligustri, Linn. No. Species. Period of Observation. Atmo- sphere. Insect. Differ- ence. Pulsa- tion. 1834. , „ o o o 1 Sphinx ligustri, larva... Aug. 29. a.m. 11 15 66-8 67-3 •5 27 2 Sphinx ligustri, larva... A.M. 11 30 67-6 6S-0 •4 27 3 Sphinx ligustri, larva... A. M. 11 40 67-8 68-1 •3 28 4 Sphinx ligustri, larva... A.M. 11 45 68-0 68-2 •2 29 5 Sphinx ligustri, larva... A.M. 11 50 68-4 68-6 •2 30 6 Sphinx ligustri, larva... A.M. 12 0 68-5 68-6 •1 30 •7 Sphinx ligustri, larva... A.M. 12 8 68-8 68-9 'I 31 8 Sphinx ligustri, larva... A.M. 12 15 69-1 69-1 •0 32 9 Sphinx ligustri, larva... a.m. 12 23 69-2 69-2 •0 31 10 Sphinx ligustri, larva... a.m. 12 30 69-3 69-4 •1 33 11 Sphinx ligustri, larva... p.m. 12 38 69-5 69-5 •0 31 12 Sphinx ligustri, larva... p.m. 12 45 69-6 69-6 •0 32 13 Sphinx ligustri, larva... p.m. 12 50 69-7 69-7 •0 32 14 Sphinx ligustri, larva... P. M. 1 0 69-7 69-7 •0 32 15 Sphinx ligustri, larva... P. M. 1 8 69-8 69-8 •0 32 16 Sphinx ligustri, larva... P.M. 1 15 69-9 69-9 •0 32 17 Sphinx ligustri, larva... p.m. 2 0 69-7 69-8 ■1 31 18 Sphinx ligustri, larva... p.m. 2 45 69-6 69-7 •1 31 19 Sphinx ligustri, larva... p. m. 3 15 69-2 69-6 •4 30 20 Sphinx ligustri, larva... p.m. 3 30 69-3 69-8 •3 30 21 Sphinx ligustri, larva... p. m. 4 0 69-3 69-8 •5 30 22 Sphinx ligustri, larva... p.m. 4 15 69-4 89-9 •5 30 23 Sphinx ligustri, larva... p.m. 5 0 69-4 69-8 •4 29 24 Sphinx ligustri, larva... p.m. 5 15 69-4 69-9 •5 31 25 Sphinx ligustri, larva... p.m. 5 30 69-4 69-9 •5 30 26 Sphinx ligustri, larva... p.m. 6 0 69-1 69-7 •6 29 27 Sphinx ligustri, larva... p. m. 6 30 68-8 69-3 •5 29 28 Sphinx ligustri, larva... P.M. 7 0 68-7 69-6 •9 36 29 Sphinx ligustri, larva... Aug. 30. a.m. 6 0 65-0 65-4 •4 25 30 Sphinx ligustri, larva... A.M. 7 0 65-5 65-8 •3 25 31 Sphinx ligustri, larva .. A.M. 8 0 66-0 66-3 •3 24 32 Sphinx ligustri, larva... A.M. 9 0 67-4 26 33 Sphinx ligustri, larva... Aug. 31. A.M. 11 0 66-6 67-0 •4 18 34 Sphinx ligustri, pupa... Sept. 4. a.m. 10 0 66-1 66-4 •3 12 Faces. Loss. Age. Remarks. grs. grs. ges. 7th day. 61 141-4 136-6 110-4 79-4 3-5 Skin. 3-8 27-2 8th day. 9th day. 13th day. f After last change of skin, { sleeping. Sleeping. Sleeping. Sleeping. Sleeping. Sleeping. Sleeping. Sleeping. Sleeping. Sleepi ng,but slightly aroused. Sleeping. Sleeping. Sleeping. Sleeping. Sleeping. Sleeping. Sleeping. Sleeping. Sleeping. Sleeping. Sleeping. Sleeping. Sleeping, f Arousing, changing co- \ lour for transformation. Sleeping. Sleeping. Sleeping. Aroused and active. Sleeping. Sleeping. Sleeping, much discoloured. Aroused, very active, f Just entered the earth, \ very active. f Pupa within one hour < after changing, has been [_ much disturbed. 4. Hybernation. From a state of profound sleep we pass to that of hybernation, which, as shown in the hybernating Mammalia*, appears to be almost identical with the natural repose of all animals. In insects, however, hybernation seems to differ from natural rest in some of its exciting causes. Thus there are reasons for believing that this disposi- tion to pass into a profound sleep, bears some relation to the changes which take * Dr. M. Hall, Philosophical Transactions, 1832, Part I. MDCCCXXXVII. 2 O 276 MR. NEWPORT ON THE TEMPERATURE OF INSECTS. place at certain periods in the capacity of the respiratory organs, which seem to be- come oppressed, and their full expansion prevented by the remarkable accumulations of fat which always exist in the bodies of insects before passing into the true hyber- nating condition. Thus before the larva assumes the condition of pupa it feeds most voraciously, and an immense quantity of fat is collected within it, and if it has been properly supplied with food, it acquires its utmost size and weight many hours be- fore it changes to a pupa. During the interval which elapses between its full deve- lopment as a larva and its change into the pupa state it is often much less active, and has the appearance of an animal suffering from repletion : it ceases to eat, it is more sluggish in its movements, often sleeps a great deal, and perspires copiously ; its average temperature is lower than it had been a day or two previously, and its quan- tity of respiration is also diminished. These appear to be conditions which induce the phenomena of its transformation, because I have repeatedly found that if a larva be deprived of its proper quantity of food, its change into the pupa state does not take place so early, but is retarded for two or three days. On the other hand if the insect be supplied to repletion, its change will be slightly hastened. Thus if several specimens of the larva of the Sphinx be hatched at about the same time but supplied with different kinds of food, those which are fed upon one kind of plant will often arrive at maturity and undergo their changes before those which are fed upon another. In these cases it is inferred that a plethoric condition, which is supposed always to precede the change to the pupa state, occasioned by the accumulated fat within the body compressing the respiratory organs, and thereby preventing the full aeration of the circulatory fluids, is induced in the one instance earlier than in the other, owing to the more nutritious quality of the food supplied to the insect during the first few days after it has left the egg*. There is also another strong reason for believing that this condition of body is closely connected with the phenomena of transformation, in the circumstance that, although for many hours immediately preceding the change, the quantity of respiration, relatively to the size of the insect, becomes diminished, yet within one hour of the actual period of rupturing and throwing off its skin, the insect makes several very powerful and laboured inspirations ; and it is then probably that those tracheae which seem to have become compressed and diminished in calibre during the plethoric state, begin again to be distended, previously to their subse- quent development into the large respiratory sacs of the perfect insect. This enlarge- ment of the sacs is slowly progressive during the earlier, but most rapidly so during the latter period of the pupa state, while particularly in the Sphinx, it is almost sus- pended in the middle, or intervening period of this state, the period when the insect is in its most complete state of hybernation. The enlargement, as suggested on a former occasion*, seems to keep pace with the gradually diminishing size of the alimentary canal, and with the absorption of the accumulated fat, and since it is well known that a higher or lower degree of atmospheric temperature will either accele- rate or retard the completion of these changes in the pupa, it may not be unreason- * Philosophical Transactions, 1836, Part II. p. 534. MR. NEWPORT ON THE TEMPERATURE OF INSECTS. 277 able to infer that the subsequent arousing of the insect from this hybernating condi- tion arises, in addition to the stimulus of increased temperature in the surrounding medium, partly also from the stimulus of a more perfect aeration of its fluids, through means of the greater quantity of air which necessarily enters its enlarging respiratory organs. These opinions are supported by the facts that some insects pass into the pupa state at two different periods of the year, and that their subsequent development into the perfect state depends upon the period at which they enter into the pupa. Thus the common Cabbage Butterflies, Papilio brassicce, Linn., and P. Napi, Linn., when changed from larvae to pupae in the middle of summer, become perfect insects within a fortnight ; but when the change into the pupa state takes place at the end of summer, the perfect insects are not developed until the following spring, unless, as shown long ago by Reaumur, they are placed in a warm atmosphere, when they may at any time be developed within a few days, even in the months of December and January. Besides these facts, and a variety of others which are equally well known, every one is aware that the hybernation of many insects occurs at compara- tively high degrees of temperature. The facts connected with the presumed plethoric condition of insects before hybernating are equally referable to those perfect insects which pass the winter months in hybernacula as to larvse which are about to pass into the pupa state, since it is found that they always have a much larger accumula- tion of fat in the autumn than at other seasons of the year. This is the case in the bodies of Vanessa Atalanta, Steph., V. Io} Steph., V. urticce , and in the Cabbage But- terflies just noticed ; and it is well known to the cottager that when the flowers have not yielded an abundance of honey in the latter part of the summer, the bees in his hives will have less chance of existing through the winter than when the production of honey has been plentiful. This latter circumstance may, perhaps, be said to arise from a deficiency in the quantity of honey stored up by the bees, but I have strong reasons for believing that it arises chiefly from the bees being in a worse bodily con- dition, and having but a small quantity of nutriment stored up within their own systems, which alone enables them to pass some portion of the winter in a state of repose. If the female of the common Humble Bee, Bombus terrestris, Steph., which sleeps through the winter andAppears early in the following spring, be examined about the end of September, its abdomen is found to be supplied with large bags of fat. At that period the insect is less active, and evolves a smaller quantity of heat than in the spring when there is a much lower temperature of the atmosphere. And if at that period the insect be deprived of food it will continue to live, very much longer than it would have lived, under similar circumstances, and exactly at the same tem- perature of the atmosphere in the month of April. About the end of September I confined two large females, Bombus terrestris and B. lapidarius , Steph., in the same box without food, and placed them in my sitting room, the temperature of which was seldom lower than 60° Fahr. and often 65°, during the whole time of their confine- ment. When first confined they were both very active. B. terrestris died on the 27th of October, and B. lapidarius on the 5th of November, having each of them been confined about a month or five weeks. Now the very same species when confined in 2 o 2 278 MR. NEWPORT ON THE TEMPERATURE OF INSECTS. the early part of the spring and summer, at a temperature of at least 10° lower than the present, would have perished within forty-eight hours. Hence it is not diminished temperature alone that induces a state of hybernation. Now during the confinement of these individuals I examined other specimens of the same species, and found the abdomen in each of them well filled with fat, while the respiratory organs appeared to be diminished in calibre, and somewhat compressed by its accumulation. This was particularly the case with one specimen which I examined, and the circumstance became the more interesting to me from a knowledge of the fact that both the amount of respiration and the quantity of heat evolved by the insect are at this period dimi- nished. But without going further with the causes of hybernation of insects, and which do not directly belong to this subject, it may be inquired how it happens that if the sleep of the hybernating insect be induced by a plethoric condition of body, that there are certain species, as, for instance, the Anthophora retusa, Steph., which assume the perfect form and begin to hybernate during the summer, even at the end of August, but do not leave their abodes until April or May in the following spring, although the morning sun shines brightly on their dwellings, and sometimes raises the exterior surface of the bank in which they are deposited to a temperature of 80° Fahr. or upwards ? Unto this it may be replied that the bodies of those insects, having so recently changed from the larva to the perfect state, are still provided with a full supply of nourishment ; that the soil in which they are nidificating has not its tempe- rature increased to a sufficient depth to arouse them into activity, and that even if its temperature be sufficiently increased for a day or two, it does not continue at the same standard, but gradually declines with the approach of autumn ; while on the other hand, on the approach of spring the mean temperature of the atmosphere is daily augmented, and the insect becomes aroused from its long slumbers by the steadily increasing warmth of its dwelling ; its respiration is then excited, its fluids circulate more quickly, and the nutriment stored up within its body when it entered its sleeping condition having become exhausted, it is soon stimulated by the calls of hunger*, which the more perfect aeration of its fluids and the activity of all its func- tions induce within it ; it makes a powerful effort to escape from its prison house, and pioneers its way through the soil to a new life, a life of activity, — directed in its proper course by the less consolidated state of the earth, in the passage to its abode, with which, many months before, the careful parent bee had securely closed the entrance, to protect her delicate offspring from the intrusion of enemies. I have seen this insect at the moment of its first leaving its abode. It always takes several very deep and powerful inspirations before it first takes wing, and its temperature is then scarcely more than a degree or two above that of the nidus it has just left. The comparative amount of the temperature of this insect in its different states during the period of hybernation, as compared with the temperature of the soil in which it is living and with its temperature in the perfect and active period, is very interesting, and will best be shown in the accompanying Table. * Dr. M. Hall on Hybernation, Philosophical Transactions, 1832, Part I. p. 22. ME. NEWPORT ON THE TEMPERATURE OF INSECTS 279 280 MR. NEWPORT ON THE TEMPERATURE OF INSECTS. From this Table it is seen that in the autumn, while the larva of the Anthophora continues active in its cell, its temperature is higher than that of either nymph or perfect insect, while the nymph, which has in reality a lower temperature than either the larva or perfect insect, being at that time in a state of activity, or degree of ex- citement inferior to that of the larva, and superior to that of the perfect insect, has a temperature in its cell intermediate between that of these two conditions. It was evident to me while making these observations that these apparently contradictory facts arose only from the circumstance of the perfect insect being then in a state of far more complete hybernation than the nymph, which, as well as the larva, was less able to maintain its temperature when raised to a certain amount than the perfect insect. But when the season of hybernation is over, and the swarthy female bee is roving abroad in the sunshine of the months of May and June, she has a temperature, as shown at Nos. 18, 24, 35, 37, and 38, very far above her temperature in the states of larva and nymph, or than what is possessed by her only a short time before she quits her cell in the months of March and April, when her temperature is scarcely higher than that of the larva, as shown in Nos. 15, 16, and 17- But if the perfect bee be taken from her cell either at the end of March or at the commencement of her hybernation in September, her temperature of body after a few inspirations will be raised to two or three degrees above that of the atmosphere, but if undisturbed the insect always endeavours to sink again into a state of repose, and the temperature of her body becomes that of the surrounding medium. The soil in which the hyber- nacula of these insects are formed being of sand or clay, which are bad conductors of heat, always continues of a more uniform temperature than the open atmosphere, and is less subject to variations through the alternating and often suddenly changed tem- peratures of day and night, so that the insects are neither exposed on the one hand to the chilling hoar frosts of midnight, nor to the scorching sun of noon, which even in April, as shown on the Table, Nos. 16 and 17, may raise the thermometer to 8]°Fahil on the surface of the bank, while the insects in their nidi at only 1^ inch or 2 inches deep are preserved in an almost uniform temperature of 56° Fahr. ; and when the perfect insects have left their dwellings and are again filling the bank with cells and storing them with ova and with honey-paste for the support of the future young, the temperature of the same cells may be raised to 80° or upwards, a temperature which perhaps is then necessary for hatching the ova, and rearing the larvae in their earliest condition. 5. Inordinate Excitement. The great rapidity with which, as we have just seen, the temperature of an insect is raised from being almost on a level with that of the surrounding medium to several degrees above it, would naturally lead us to conclude that a much larger amount of heat is in reality generated than what is indicated by the thermometer, and that since the heat evolved within the body of the insect becomes perceptible through means of MR. NEWPORT ON THE TEMPERATURE OF INSECTS. 281 the thermometer so very rapidly, it is fair to suppose that the insect parts with it with nearly equal facility, and that a very large proportion evolved passes off to the sur- rounding atmosphere or medium in which the insect is inclosed, and that when such medium is of given small extent its temperature becomes raised as well as that of the insect, and is appreciable by the thermometer. This is in reality the case ; and Dr. Burmeister* has already imagined it to be so, but he does not appear to have made any observations of his own in order to prove it, but refers to the observations before noticed by Hausmann^. I remarked the fact during my earlier observations on the temperature of insects in 1834, when endeavouring to ascertain the actual amount of temperature in the common Humble Bee in a state of rest and in a state of great excitement, and when endeavouring also to ascertain whether the amount of temperature in a single insect is equal to that of an indefinite number of individuals. I had long suspected that this could not be the case, and that, for instance, the tem- perature of a hive of bees in winter, stated by Huber to be equal to 80° Fahr., could not be equal to that of a single individual at the same period. Previous observations had induced me to believe that the temperature of a single insect is only a few degrees above that of the medium in which it is living, and that the actual heat of the insect is increased in proportion to the amount of its respiration ; that when an insect is at rest its temperature is comparatively low, and that it becomes greatly increased during violent activity ; and further, that a number of individuals confined in a given space can raise the temperature of that space to a great amount. With these views I in- closed a single female of Bombus terrestris in a glass-stoppered phial of three cubic inches capacity, having first noted the temperature of the atmosphere within the phial, and of that of the external atmosphere immediately around it, both of which stood at 660,9 Fahr. The bee was allowed to remain about five minutes in the phial in a state of great activity, and its temperature was then taken by pressing the bulb of a thermometer against its abdomen. The mercury rose to 73°'4 Fahr., or 60,5 above the temperature of the atmosphere, while the temperature of the atmosphere of the phial was raised to 68°‘2 Fahr., or 20,3 above that of its original temperature. Three other individuals of the same species were then added, and the whole four continued in a state of excitement until the mercury rose to 74°‘5. It was thus proved that a single individual when excited raises the temperature of the surrounding medium, and that several individuals collectively will increase the temperature of that medium beyond what it could possibly be increased by only one. In the next experiment, the atmosphere being 69°‘4 Fahr., five individuals of the same species were confined in the same sized phial as the one just employed, and after remaining in a state of great excitement raised the temperature of the phial to 7 20,5, a difference of 3°T, while the temperature of the five excited bees was 76°‘3. In an- other experiment, when a single bee was allowed to remain at rest with the thermo- * Manual of Entomology, p. 403. Translated by W. E. Shuckabd, Esq. M.E.S. 1836. f De Anim. Ex. Respirat. p. 68. 282 MR. NEWPORT ON THE TEMPERATURE OP INSECTS. meter pressed against its abdomen until it had become perfectly quiet, the mercuiy rose only to about one degree above that of the surrounding medium. These experi- ments appeared to indicate that the quantity of heat evolved is in the ratio of the degree and activity of respiration. On the 9th of June 1834 three female specimens of Bombus terrestris, B. lapidarius, and B. muscorum, all of which had been captured about three hours previously, were submitted to experiment, great caution being taken to prevent anything from inter- fering with the correctness of the observations. The temperature of the atmosphere and of the phials employed on this occasion was 68° Fahr., and the time occupied in each observation was five minutes. Bombus terrestris raised the temperature of the phial to 72° Fahr., and maintained it at that height during the whole of the experi- ment, while the temperature of its own body was 77° Fahr. That of B. lapidarius at the end of the observations was 71°'5, and of B. muscorum 7 2°-2 Fahr. In the first of these observations the temperature of B. terrestris was gradually raised from the tem- perature of rest, or only two or three degrees above that of the atmosphere, 68° Fahr., to 77°- During the whole five minutes the insect continued in violent motion, and maintained the temperature of the stoppered phial at 72°, or 4° above the temperature of the phial at the commencement of the observation, while that of the insect itself was raised to 9°, or 50,5 above that of the medium around if, which it had itself raised 4°. At that time I imagined that this great amount of temperature, nearly 10° Fahr., was very nearly or quite the maximum amount of temperature that a single insect can generate, since a little more exertion, or longer continuance of excitement, would have made the insect perspire copiously. The occurrence of this phenomenon in in- sects, as in vertebrated animals, must be looked upon as the natural cooling process, and beyond which the temperature of the animal cannot be raised in a state of health. The second specimen, B. lapidarius, was feeble, and only in a moderate state of ac- tivity, and consequently did not raise the temperature of its body above the usual standard. The third specimen, B. muscorum , was very much excited, and its tem- perature rose to 72°’2, or 4° above that of the atmosphere. On the 9th of July 1834, atmosphere 690,8 Fahr., I placed a single specimen of B. Jonella immediately after it was captured in the stoppered phial employed in the previous experiments. The phial was closed, and the insect continued in a highly excited state for six or eight minutes. When it had become quiet a thermometer was very carefully introduced to the bottom of the phial without touching the insect, and the mercury rose to, and was main- tained at 74°’7, or 50,8 above that of the atmosphere and of the phial at the com- mencement of the observations. The insect then became excited, and the thermo- meter was held near enough to touch the tips of its wings. The temperature of the air in the phial immediately sunk to 72°'5, being a diminution of 20,2. This observa- tion was several times repeated with the same results, so that while confirming the previous conclusion respecting the evolution of heat, it shows also another interesting fact, viz. that the vibration of the wings tends to cool the body of the insect during MR. NEWPORT ON THE TEMPERATURE OF INSECTS. 283 flight, and moderate its temperature. But the power of radiating from its body into the surrounding atmosphere is not confined to the insect in its perfect state only, but exists also in the larva, as I have had opportunities of observing in the larvse of the Sphinges, Puss Moth, &c. From these observations it is clear that a very large pro- portion of the heat evolved by insects in all their states passes off into the surrounding medium, and that the amount of heat evolved is in proportion to the degree of excite- ment and consequent quantity of respiration. III. Temperature of different Tribes of Insects. Having found that every insect maintains its own temperature of body, and that the amount of this temperature differs in the different states of each insect, it yet re- mains to be seen which are the families that generate the greatest amount, and what relation that amount in the different families bears to the habits and localities of the species. Our previous observations lead us to anticipate the fact that the volant insects in their perfect state have the highest temperature, while on pursuing the inquiry it is found that those species which have the lowest temperature are con- stantly located on the earth. Among the volant insects, those hymenopterous and lepidopterous species have the highest temperature which pass nearly the whole of their active condition on the wing in the open atmosphere, either busily engaged in the face of day despoiling the blossoms of their honied treasures, or flitting wan- tonly from flower to flower and breathing the largest amount of atmospheric influence. Of these it may be almost superfluous to remark, the Hive Bee and its long train of near and distant affinities, and the elegant and sportive Butterflies have the highest. Next to these probably are their predatory enemies the Hornets and Wasps, and others of the same order ; and lastly, a tribe of insects which have always attracted attention, and in general are located on the ground, but sometimes enjoy the volant condition, — the Ants, the temperature of whose dwellings has been found to be considerably above that of the atmosphere : according to Juch the temperature of an ant-hill was 17° Reaum. (70o,25 Fahr.), while that of the atmosphere was 10° Reaum. (540,5 Fahr.). Next below the diurnal insects are the crepuscular, the highest of which are the Sphinges and Moths, and almost equal with these are the Melolonthce. But the fol- lowing experiments with the different tribes, while they still further illustrate the causes of the variability of temperature in insects, will also show the relative amount of heat evolved by different species. Melolontha vulgaris, Steph. May 20, 1835, 7 a.m. — Having captured many individuals of this species of Chaffer Beetle on the preceding evening, I now found them perfectly quiet. The temperature of the external atmosphere was 60° Fahr., and that of the interior of the box in which they had been confined during the night was 610,3, while on carefully introducing the bulb of the thermometer among the beetles, without disturbing them, the mercury mdcccxxxvii. 2 p 284 MR. NEWPORT ON THE TEMPERATURE OF INSECTS. rose to 610,5 F. I then took a single beetle which had been remaining quiet, and having secured him with the forceps, opened the abdomen quickly with a pair of scissors, and introduced the bulb of a fine thermometer. The mercury immediately rose to 63°"3 Fahr., a difference of 2° above the temperature of the box, and 3°°3 above that of the atmosphere, and it was maintained at that height more than ten minutes, after which it sunk two or three tenths of a degree, as the energies of the insect became impaired. Half an hour after the above observations the temperature of the box had risen to 63° Fahr., and the insects were in motion; and when the bulb of the thermo- meter was merely allowed to rest upon the backs of several specimens, the mercury rose immediately to 650,3 Fahr. When the beetles were again examined on the 23rd of May, at 7 a.m., they were perfectly quiet, having fasted since the last observation, being now a space of eighty-two hours since they were captured and had taken food. Atmosphere 60°‘5 Fahr., of the box with the beetles 610,3, thermometer introduced carefully among the beetles 610,5, but when introduced as above into the body of a single beetle it rose to 630,3 Fahr. One hour after this, at 8 a.m., atmosphere 64°, the temperature of the box was 66°, and the temperature of the interior of the body of a quiet beetle was 69°”2. At 8^ a.m., atmosphere 640,5, thermometer applied to the exterior of the body of a female beetle that had been respiring very rapidly and preparing for flight, the mercury rose to 69°’3, and continued to rise in proportion to the degree of respiration of the insect. At 8f a.m. the insect just employed was placed on its back for half an hour, during which time it was respiring very rapidly, and endeavouring to escape, and its temperature had risen at the expiration of this period to 740,5, while that of the atmosphere was G5°‘5, a difference of 9°, so that although this insect had now been entirely without food for nearly eighty-four hours, its long abstinence had very little diminished its power of generating heat. A male specimen was then placed under almost precisely similar circumstances, and its tem- perature rose to 74°. At 6 p.m., atmosphere 64°T, the same female specimen which had been employed in the morning, but which subsequently had been lying at rest for several hours, and was still reposing, had a temperature of 6G°‘3, a difference of only 20-2, while the same male specimen that had been employed in the morning and had since been at rest, but was now respiring again very freely, and attempting to escape, had a temperature of 690,1, a difference of 5° above that of the atmosphere, thus fairly leading to the inference that the amount of temperature is in proportion to the quantity of respiration. At 7 p-m. May 24. — The temperature of a female specimen which had been at rest since the morning in its natural haunts clinging to the leaves of a lime tree was very carefully taken without disturbing it, by applying the thermometer to its abdomen, and was found to be only 62°’6, or one tenth of a degree only above that of the atmosphere ; so that, like the temperature of the hybernating Mammalia, it had sunk down during its rest almost to a level with that of the surrounding atmosphere. MR. NEWPORT ON THE TEMPERATURE OF INSECTS. 285 Melolontha solstitialis, Steph. June 26, 1834, a.m. — The specimens employed on the present occasion were cap- tured on the evening1 of the 25th, the temperature of the atmosphere being 70°*5 ; a single specimen, which had been lying for some time at rest, had a temperature only of /0°'8. Five specimens which had previously been very active, and were now per- spiring profusely, raised the temperature of a phial, whose cubic bulk was about two inches, from70o-5 to 71°‘4. Nine insects in a similar-sized phial raised the tempera- ture in four minutes from 70o,5 to 72°*2, and a few minutes afterwards to 730,2. During this time the insects were in a state of the greatest excitement. The bulb of the ther- mometer was not brought into contact with the bodies of the insects. When the thermometer was placed among the beetles, and in contact with their bodies, the mercury rose to 74°*5, a difference of at least 4° above the original temperature of the bottle ; but this was far from being the full amount of the heat of these insects. During these observations I found that a large amount of heat generated by the in- sects confined in the phial becomes latent, and also that much caloric is radiated from the exterior of the phial, which becomes heated by the beetles and warm air within, as is proved by the fact that when the thermometer is held very close to the side of the phial without touching it, the mercury is considerably affected, and when the bulb of the thermometer is held in contact with the phial the mercury ascends the scale. In the present experiment it rose more than a degree when the bulb of the thermometer touched the side of the phial. It must not be forgotten that besides this difficulty in our observations on the temperature of insects, there is another which prevents us from knowing the exact amount of heat generated by the insect under examination. It is seen in these observations on the Melolonthce, as before shown in the Bombi, that a large amount of the heat generated by the body of an insect quickly .passes off into the surrounding medium. But if the excited state of the insect be ex- cessive, and the consequent evolution of heat greatly exceed its usual amount, nature has resorted to another expedient for cooling down the animal body, through means of a profuse perspiration, which is carried on in insects perhaps to a greater extent than in other animals. Thence the amount of heat believed to be generated under certain conditions is only comparative ; but when, as in experiments made on many specimens collected together, a profuse perspiration breaks out among the insects, the amount of temperature indicated by the thermometer introduced among them is much lower than the real amount that has been produced. This was the case in the present instance : the specimens were in a state of profuse perspiration, besides which they had fasted about eighteen hours. These facts were further illustrated by a sub- sequent experiment, in which eighteen specimens were employed in the same sized phial ; they were crowded together, and allowed to remain about a quarter of an hour in a state of great activity, until they became gradually weakened, were bathed with perspiration, and were becoming quiet and asphyxiated with the carbonic acid 2 p 2 286 MR. NEWPORT ON THE TEMPERATURE OF INSECTS. gas produced during their confined respiration. The temperature of the atmosphere of the phial at the commencement of the observation was 7 1°‘3, at the termination 730,2, a difference of only 1°‘9. Lucanus cervus, Linn. July b, 1834, 9 a.m. — The temperature of the atmosphere being 67°, that of a male specimen of this insect, the great Stag Beetle, which had been fasting about two days, was very carefully taken while the insect was lying at rest, by placing the bulb of the thermometer for several minutes against the surface of its abdomen. The mercury rose to 67°'3, a difference of only -3 of a degree of external temperature. At 9^ a.m. I inclosed the insect in a stoppered phial of about three cubic inches capacity. The temperature of the atmosphere and of the phial was 660,9. The insect remained per- fectly at rest for a quarter of an hour, at the expiration of which the atmosphere of the phial was 67°‘l. At the expiration of half an hour it was 67°'2, and the external temperature of the insect itself was 67°*4. During this period the insect had remained perfectly quiet, but at the expiration of an hour it began to find itself uneasy, and became slightly active, probably from the presence of carbonic acid gas in the phial, which had been generated during respiration. At 10| the atmosphere of the phial was raised to 68°‘5, or 10,5 higher than at the commencement of the observation. The temperature of the atmosphere was now 660,6. The insect was then removed from the phial, and the bulb of a delicate thermometer passed beneath its elytra, and the mercury rose to 68°‘2. The insect was then placed on its back upon a smooth table, which occasioned it to exert itself greatly in order to recover its proper position. The bulb of the thermometer was applied as before, and the mercury rose to 690,2, or 20,6 above that of the atmosphere. At 4 p.m., atmosphere 7 1°> temperature of the insect beneath the elytra as before, was 7 10,5. Coccinella septempunctata, Linn. It is almost impossible to ascertain with any precision the temperature of these interesting little insects, the Lady Cows, but I have sufficient reason for believing that it is very considerable, and corresponds with the views which ought to place them in the class of volant diurnal insects of high temperature. Had a larger number of specimens been employed, I have no doubt that the amount of heat evolved would have corresponded with the very high degree of respiration which they are found to possess. July, 9 a.m., atmosphere 67°‘l, eight specimens were confined in a cubic inch phial, the temperature of which was 68°*2 , and when four of them were clinging to the bulb of the thermometer the mercury immediately rose, and was maintained at 68°-5, and after a short interval, when the insects had been moderately active, the thermometer stood at 69°, a difference of nearly one degree. MR. NEWPORT ON THE TEMPERATURE OF INSECTS. 287 Meloe proscarabceus and M. violaceus, Linn. These insects (the Oil Beetles), like their congeners the Blister Beetles (Lyttce), have a temperature corresponding to their natural habits. The temperature of a number of Lyttce vesicatorice was found by Juch to be several degrees above that of the atmosphere. This, to a certain extent, is the case with the Meloes, which love to bask in the heat of the sun, and respire a large quantity of atmospheric air. On the 1st of May I examined the temperature of a female Meloe proscarabceus soon after it was captured, and found its temperature amounted to very nearly 3° above that of the atmosphere when the insect was a little excited ; but half an hour afterwards, when the insect had become more calm, it had subsided to 1°*5. I have in general found that the temperature of a single Meloe varies from one to two degrees above that of the atmosphere when not excited, and it seldom sinks down to the temperature of the atmosphere, because during the season in which the perfect Meloe is found it is almost always active. But when the newly developed Meloe first leaves its nidus in the earth in the beginning of March or end of February, I have seldom been able to detect more than one, or at most two tenths of a degree, in those of one species which I have had opportunities of examining, Meloe cicatricosus ; and the same is the case with the nymph of the same species found in the month of August. Gryllus viridissimus, Linn. All the Grylli or locust tribes have comparatively a high temperature, and exist but a short time when the atmosphere around them becomes vitiated. This accords with their usual habits. We find them in the most sunny places, basking in the hottest rays, or chirping among the bushes at some distance from the ground. Hence we should conclude, a priori, that they have a high temperature. In a female spe- cimen of G. viridissimus, captured on the 14th of July, when confined for a short time, atmosphere 73°'75 the temperature of the air of the phial had risen to 74°'7> and that of the insect at rest to 750,4, but when excited 75°’8, a difference of 2°T. When the insect had been confined in a phial about an hour it respired at the rate of 37 irre- gular and forcible contractions per minute. It was then becoming affected by the carbonic acid in the phial, the atmosphere of which had been raised to 74°‘9, while the insect was perfectly at rest. In a subsequent experiment the temperature of the insect was 76°, that of the atmosphere continuing at 7 3°-7. When the observations were repeated at 7 o’clock on the morning of the 15th, atmosphere 630-3, the tempe- rature of the phial was soon raised to 67°’4, while that of the insect not excited was 68°, a difference of 40-7. At 11 a.m., atmosphere 71°‘6, insect 73°'6, phial 7%0'7, and on the morning of the 16th at 7, the insect having fasted for thirty-six hours, atmo- sphere 69°*1, phial 70°, insect 70°'5, but when excited 70o,8, thus proving that a great diminution of its power of generating heat had taken place during its abstinence. 288 MR. NEWPORT ON THE TEMPERATURE OF INSECTS. Staphylinus olens , and S. erythropterus, Linn. Both these species of Rove Beetles have a comparatively low temperature, and it is often difficult even to detect the existence of distinct temperature in these insects, unless the individuals have become considerably excited. I have never yet examined S. Olens in the autumn before it retires to its hybernaculum, but in a specimen found in April, the temperature of the atmosphere being 60o,2, that of the insect was 610,2. I could seldom find it rise higher, and it was often difficult to detect its existence at all. In S. Erythropterus I have seldom found the temperature higher than about ’5 above the atmosphere. It must thus be seen that there is a marked difference between the power which these insects possess of generating heat, and those which are more constantly in the open air ; and when we examine the Carahi and Tenehriones , this difference of power is still more remarkable. Cardbus monilis , C. violaceus, and C. nemoralis, Linn. June 18, 1834. — A specimen of the Ground Beetle, Car abus monilis, without being touched with the fingers, was carefully placed in a stoppered phial, the temperature of which, as well as of the atmosphere, was 670,4. When the bulb of the thermo- meter was pressed against the under surface of the insect the mercury was not per- ceptibly affected, nor was there any change in the temperature of the closed phial during five minutes, all which time the insect was in a state of great excitement. This observation being made precisely as in the cases with the hymenopterous insects, the temperature of the Carabus, consequently, is exceedingly low. It ought to be remarked, however, that this insect had fasted during eighteen hours, and of course could not be expected to generate so great an amount of heat as the recently fed specimens. A second specimen, which had been recently captured, was then placed with the first in the same phial, and within a few minutes the atmosphere of the phial was raised to 6 7°‘6, or -2 of a degree above the previous'temperature. A specimen of Carabus violaceus was then added to the number, and the three insects continued in a state of great excitement for several minutes, when the inside of the phial was found to be 67°'7, or '3 of a degree above its original standard; but only a very slight additional effect was produced on the thermometer when applied to the body of the insects. April 11, 1836, 3^ p.m. — I examined a single female specimen of Carabus nemoralis which had recently been captured. The insect was lying quiet when I made the first observation, by applying the thermometer to the under surface of its abdomen. The temperature of the atmosphere was then 61°‘6, and that of the insect 610-8. The insect then became active, and at the expiration of half an hour was 620,8, that of the atmosphere having risen to 620,5, while in ten minutes after this observation, the atmosphere being 63°, that of the insect was 630,4. The difference, therefore, in this specimen in a state of great excitement, was only *4 of a degree, while, as we have MR. NEWPORT ON THE TEMPERATURE OF INSECTS. 289 before seen, the difference in a Hymenopterous or Lepidopterous insect, in the per- fect state, and under precisely similar circumstances, would have amounted to at least eight or ten degrees. From these observations it is evident that the natural heat of the Carabi is exceedingly low, and that their external temperature is scarcely more than *2 or -3 of a degree above that of the medium in which they are living; and although the respiration of these insects is higher than might at first be supposed from the small amount of their external temperature, yet they have the power of bearing the privation of oxygen for a very long time, and also of supporting the presence of some noxious gases ; while they often reside in the coldest, dampest, and most unaerated situations. It was a specimen of this species that I once kept for several hours in hydrogen, and at the end of the observation found that it had ex- pired a considerable quantity of carbonic acid gas during its confinement. Blaps Mortisaga, Linn. June 26, 1834. — The temperature of this species (which is truly a nocturnal one,) appears to be lower even than that of the Carabus. I placed two specimens in a phial, the temperature of which, and of the surrounding atmosphere, was 71°; but the thermometer was raised only T of a degree, even after the insects had been for a considerable time in a state of activity. Two more specimens were then added, and the four insects were in a state of great activity for five minutes, when the tempera- ture of the phial was only 7 1°*1, that of the insects themselves 7 10, 4, a difference of only '4 of a degree above the medium in which they were confined. Thus the amount of power of developing heat in the Blaps, as in the Carabus , corresponds with the capability of supporting existence in a noxious medium, and also with its power of sustaining life during long abstinence. The Blaps will live for several minutes in a mixture of the most noxious gases, carbonic and even nitrous acid gas. I have con- fined one of this species in nitrous acid gas for three minutes, and it recovered in a quarter of an hour after being again exposed to the atmosphere. Another specimen was confined in nitrous acid gas for fifteen or sixteen minutes, and although it did not give any indications of recovering after being again exposed to the atmosphere for more than an hour, yet on my beginning to dissect the specimen, and after I had removed the whole under surface of the abdomen it began to recover, and in less than four minutes was so completely restored as to be able to walk about with nearly its usual speed. I have also confined other specimens in hydrogen for several hours, during which time they evolved a considerable quantity of carbonic acid gas, and did not appear to be at all inconvenienced by the medium in which they were placed. The low amount of heat in the species corresponds also with its power of going without food. One of this species is stated to have lived three years in confinement without food, and I have myself kept several individuals of this species about nine months fasting ; it must be remarked, however, that this was during the winter months, from the latter part of autumn to the following spring, and may derive some 290 MR. NEWPORT ON THE TEMPERATURE OF INSECTS. explanation from what is now known with regard to the condition of insects during the season of hybernation. Yet I have also kept this insect nearly three months without food during the summer, the season of activity, but it has generally died at the expiration of that period. These observations on different species will sufficiently show the great difference which exists between volant and creeping insects, in the power which they possess of generating heat, while, comparing all the physiological conditions of the species with each other, they seem to point to the source or cause of the development of heat. Thus the amount of heat is found to approach very nearly in volant Coleoptera to the amount in Hymenoptera. In both these tribes of insects the organs of respiration are of large extent, and the quantity and activity of respiration in both are great, while the quantity of heat developed appears to be in proportion to the quantity of respiration. Further, these observations lead to the conclusion that some of the volant Coleoptera ( Melolonthce ) have a higher temperature, even in a quiescent state, than some of the terrestrial Coleoptera in a state of moderate activity, while the amount is increased in a much greater degree in volant insects in a state of activity, than in those Cole- optera which live entirely on the ground. It also appears that the temperature of Crepuscular insects, Melolonthce , Sphinges, See. is lower than that of the diurnal Hy- menoptera, and this we might naturally expect would be the case. Crepuscular in- sects having, compared with their size, a lower degree of respiration than Hymeno- pterous insects, nearly all of which are diurnal species, and bear the privation of atmo- spheric air with greater difficulty than any other tribes. MR. NEWPORT ON THE TEMPERATURE OF INSECTS 291 Table IV. A Table exhibiting the Temperature of Insects of different Species under various cir- cumstances, and in their different states, compared with the Temperature of the Atmosphere at the time of making the observation. Division 1. Volant Insects, (a.) Diurnal Species. No. of Exp. Order. Species and state. Period of observation. No. of Specimens. Atmo- sphere. Insect. Difference. Remarks. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 2] 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 Hymenoptera, 1834. Hymenoptera, 1834. Hymenoptera, 1834. Hymenoptera, 1834. Hymenoptera, 1834. Hymenoptera, 1834. Hymenoptera, 1834. Hymenoptera, 1834. Hymenoptera, 1834. Hymenoptera, 1834. Hymenoptera, 1834. Hymenoptera, 1834. Hymenoptera, 1834. Hymenoptera, 1834. Hymenoptera, 1834. Hymenoptera, 1834. Hymenoptera, 1834. Hymenoptera, 1834. Hymenoptera, 1834. Hymenoptera, 1834. Hymenoptera, 1834. Hymenoptera, 1834. Hymenoptera, 1834. Hymenoptera, 1834. Hymenoptera, 1834. Hymenoptera, 1834. Hymenoptera, 1834. Hymenoptera, 1834. Hymenoptera, 1834. Hymenoptera, 1834. Hymenoptera, 1834. Hymenoptera, 1834. Hymenoptera, 1834. Hymenoptera, 1834. Hymenoptera, 1834. Hymenoptera, 1834. Hymenoptera, 1834. Hymenoptera, 1834. Hymenoptera, 1834. Hymenoptera, 1834. Hymenoptera, 1834. Bombus terrestris, perfect. Bombas terrestris, perfect. Bombus terrestris, perfect. Bombus terrestris, perfect. Bombus terrestris, perfect. Bombus lapidarius, perfect. Bombus muscorum, perfect. Bombus Jonella, perfect. Bombus Jonella, perfect. Bombus Jonella, perfect. Bombus Jonella, perfect. Bombus terrestris, perfect. Bombus terrestris, perfect. Bombus terrestris, perfect. Bombus terrestiis, perfect. Bombus terrestris, perfect. Bombus terrestris, perfect. Bombus terrestris, perfect. Bombus terrestris, perfect. Bombus terrestris, perfect. Bombus terrestris, perfect. Bombus terrestris, perfect. Bombus terrestris, perfect. Bombus terrestris, perfect. Bombus terrestris, perfect. Bombus terrestris, perfect. Bombus terrestris, perfect. Bombus terrestris, perfect. Bombus terrestris, perfect. Bombus terrestris, perfect. Bombus terrestris, perfect. Bombus terrestris, perfect. Bombus terrestris, perfect. Bombus terrestris, perfect. Bombus terrestris, perfect. Bombus terrestris, perfect. Bombus terrestris, perfect. Bombus terrestris, perfect. Bombus terrestris, perfect. Bombus terrestris, perfect. Bombus terrestris, perfect. June 7. A.M. A.M. A.M. A.M. 9. A.M. 12 A.M. 12 A.M. 12 P.M. 6 P.M. 6 P.M. 6 P.M. 8-2- 29. p.m. 5 July 10. a.m. 12 P.M. H P.M. 2-| Midnight 12§ July 11. a.m. 6 Midnight 12 July 12. a.m. 7 13. a.m. 8 a.m. 8^ a.m. 8J a.m. 9 A.M. 9 A.M. 9§ A.M. 12 P.M. 1 P.M. 2 j- P.M. 4 P.M. 10 Midnight 12 14. P.M. 1£ P.M. 2 P.M. 3 P.M. 5 P.M. 11 15. A.M. 8^- A.M. 9^ A.M. 10J P.M. 10 P.M. 11 i 5 1 5 1 1 1 1 1 1 1 1 1 4 7 7 1 7 7 7 4 1 1 1 1 1 1 4 1 1 1 1 1 1 o lo 66-9 73-4 66-9 76-2 66- 9 73-4 69- 4 76-2 68 \77-o 68 .71-5 68 172-2 68-9 74-7 68-9 74-7 69 75-4 68-2 71-3 59 | ©7*5 70- 5 77 70 80-2 70- 5 80-4 68- 5 80-3 67 ' 77-3 67- 5 78 68- 7 76-5 71- 8 84-1 72- 5 89-2 72-5 90-2 72-5 92-3 72-5 91-5 72-7 91 70- 2 92-5 72-2 85 72- 5 941 73- 5 92 69 173-5 68 I 83-2 69- 5 89-4 69- 5 92-2 69-5 91 73-4 94-2 68 183 68-2 88-2 71 91 72 '93-2 72-2 91-9 71- 6 85 o 6-5 9-3 6-5 6-8 9-5 3- 5 4- 2 5- 8 5- 8 6- 4 3- 1 8- 5 6- 5 10-2 9- 9 11-8 10-3 10-5 7- 8 12- 3 16- 7 1 7- 7 19-8 19 18- 3 22-3 12-8 21-6 19- 5 4- 5 15-2 19- 9 22-7 21-5 20- 8 15 20 20 21-2 18-7 13- 4j In each of these observations, which were all made within two or three hours of the insects being captured, the individuals were in a state of great excitement, excepting only Bombus lapidarius, which is a species that ap- pears to be less readily excited than the others. - After great excitement. Temperature ofa nest of this species containing about thirty individuals and brood comb. The nest was con- >tained in a box about seven inches square, and closed at night with a lid. Insects excited, but not in contact with the thermometer. Nurse Bees moderately excited. Nursing on a single cell, which con- tained a nymph that was developed from it about eight hours afterwards ; during this incubating the Nurse Bee respired at the rate of 120 per minute. These observations show the great power which the Nurse Bees have of producing heat at will during the pe- riod of developing the nymphs. This evolution of heat is never produced when the insect is remaining perfectly ’ quiet, but always occurs when the in- dividual is much excited and respiring very rapidly. In those cases in the Table where a small degree of heat is indicated the insect was comparatively but little excited. 2 Q MDCCCXXXVlt. Table V.— A Table exhibiting the Temperature of Insects of different Species under various circumstances, and in their different states, compared with the Temperature of the Atmosphere. Division 1. Volant Insects. (&.) Crepuscular Species. 292 MR. NEWPORT ON THE TEMPERATURE OF INSECTS. MR. NEWPORT ON THE TEMPERATURE OF INSECTS. 293 Table VI. A Table exhibiting the Temperature of Insects of different Species under various circumstances compared with the Temperature of the Atmosphere. Division 1. Volant Insects. ( b .) Crepuscular Species. Bulk in cubic ins. Weight in grains. Atmo- sphere. Insect. Difference. o o o 61-3 63-3 2- 61-3 61-5 •2 66 69-2 3-2 64-5 69-3 4-8 65-5 74-5 9- 65-5 74 8-5 64-1 66-3 2-2 64-1 69-1 5- 62-5 62-6 •1 70-5 70-9 •4 70-5 71-9 1-4 70-5 72-3 1-8 71-3 74-5 3-2 71-3 73-6 2-3 68-2 68-5 •3 68-2 69 •8 67 67-3 •3 66-9 67-4 •5 66-6 68-6 2- 66-6 69-2 2-6 71 : 71*5 •5 Order. Species. Period of Observation. °. g o 'A 8 Remarks. 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 Coleoptera. Coleoptera. Coleoptera. Coleoptera. Coleoptera. Coleoptera. Coleoptera. Coleoptera. Coleoptera. Coleoptera. Coleoptera. Coleoptera. Coleoptera. Coleoptera. Coleoptera. Coleoptera. Coleoptera. Coleoptera. Coleoptera. Coleoptera. Coleoptera. Melolontha vulgaris, perf. Melolontha vulgaris, perf. Melolontha vulgaris, perf. Melolontha vulgaris, perf Melolontha vulgaris, perf Melolontha vulgaris, perf Melolontha vulgaris, perf Melolontha vulgaris, perf Melolontha vulgaris, perf Mel. solstitialis, perf.... Mel. solstitialis, perf... Mel. solstitialis, perf.... Mel. solstitialis, perf.... Mel. solstitialis, perf.... Coccinella 7-punctata... Coccinella 7-punctata... Lucanus cervus Lucanus cervus Lucanus cervus Lucanus cervus Lucanus cervus 1835. May 23 a.m. a.m. A.M. A.M. A.M. A.M. P.M. P.M. No. 1. 1. No. 2. No. 1. No. 2. No. 3. p.m. 7 June 27 a.m. A.M. A.M. A.M. A.M. July 9 a.m. A.M. A.M. A.M. 10^ A.M. lOf P.M. 4 Male, quiet; internal temperature of body. All the specimens perfectly quiet. Quiet; internal temperature of body. Respiring quick, preparing for flight. Female. Respiration violent and long continued. Male. Under similar circumstances. Female ; has been long at rest. Male; respiring rapidly and trying to escape. f Female just taken from her natural haunts, in \ the open air in a state of perfect rest. Quiet. Very active and perspiring profusely. Very active. Very much excited. Quiet, becoming asphyxiated. The insect had been moderately active. J Very active ; had raised the atmosphere of the \ phial to 68°‘5. Insect had been lying perfectly quiet. J Perfectly quiet, but raised the temperature of the \ phial in i an hour to 670-2. J A little active ; temperature of the phial at i j- | raised to 68°-5. After great exertion. Insect has been lying quiet. Division 2. Terrestrial Insects, (a.) Diurnal Species. Proscarabaeus violaceus... April 11 p.m. 3£ 1 •04* 11 Proscarabaeus violaceus... P.M. 3f 1 •04 11 Proscarabaeus violaceus... 22 p.m. 6 1 •04 10-8 Proscarabaeus violaceus... P.M. 6jr 1 •04 10-8 Proscarabaeus violaceus... P.M. 65 1 ■04 10-8 Proscarabaeus violaceus... 23 p.m. 7 1 •05 12-7 Proscarabaeus vulgaris ... May 1 p.m. 3 1 •09 21-5 Proscarabaeus vulgaris ... P.M. 34 1 •09 21-5 Acrida viridissima 1 Acrida viridissima 1 Acrida viridissima 1 Acrida viridissima 1 Acrida viridissima 1 Acrida viridissima A.M. 1 1 1 Acrida viridissima 16 A.M. 7 1 Acrida viridissima A.M. 7 i Staphylinus olens April 23 p.m. 7 1 3-8 S. erythropterus 1 S. erythropterus 1 Coleoptera. Coleoptera. Coleoptera. Coleoptera. Coleoptera. Coleoptera. Coleoptera. Coleoptera. Orthoptera. Orthoptera. Orthoptera. Orthoptera. Orthoptera. Orthoptera. Orthoptera. Orthoptera. Coleoptera. Coleoptera. Coleoptera. 62-4 64-3 61-2 60-4 60 58-2 60-2 631 74-7 74-7 73 74-9 67-4 72-7 70 70 60-2 64-5 65 63 65 62-3 61- 7 61-2 59-3 62- 9 64- 6 75-4 75-8 74-1 76 68 73-6 70-5 70-8 61-2 65- 1 65-6 •6 •7 II 1- 3 1-2 11 2- 7 1-5 •7 1-1 11 11 •6 •9 •5 A very small female, somewhat excited. Still excited ; has been fasting. Active; has been feeding in warmer atmosphere. Has been active. A little excited. A little excited. Just after being captured; excited. Is now more quiet. Female quiet, fasting for 2 days. A little excited. {Insect confined one hour ; quiet, but respiring irregularly and forcibly at 37 per minute : du- ring this violent respiration at rest. Insect quiet. Insect a little active. A little excited ; jhas fasted for the last 4S Very much excited; J hours. Active. Male specimen ; active. Male specimen ; active. (b.) Crepuscular Species. •05 •05 •05 12-5 12-5 12-5 20 21 22 23 24 25 26 27 Coleoptera. Coleoptera. Coleoptera. Coleoptera. Coleoptera. Coleoptera. Coleoptera. Coleoptera. Carabus nemoralis Carabus nemoralis Carabus nemoralis Carabus monilis... Carabus monilis ... Carabus violaceus Blaps Mortisaga... Blaps Mortisaga... April II p.m. P.M. P.M. June 18 a.m. A.M. A.M. 26 A.M. A.M. 61-0 62-5 63 67-4 67-4 67-4 71 71 61-8 624 63-4 67-4 67-6 67-7 71-1 71-3 Female; quiet. A little active. Very much excited. J Insect was excited, but did not evolve perceptible \ heat; had fasted for 18 hours. Active. 1 n a state of great excitement. Very active. Still more active. * In my Paper on the Respiration of Insects in the Philosophical Transactions, Part II. 1836, p. 552, Table I. the cubic bulk of Carabus cancellatus, Nos. 33 and 34, and of Meloe violaceus, No. 36, has been erroneously printed 0-4 instead of 0-04. o o 294 MR. NEWPORT ON THE TEMPERATURE OF INSECTS. IV. Temperature of Insects which live in Society. We pass now to those insects which live in society, all of which belong to that great division the Hymenoptera, which have been shown to possess the highest tempera- ture and greatest amount of respiration. Naturalists hitherto have examined only two genera of this great division with reference to the subject of temperature of these insects in their dwellings. These are the Apis Mellifica, or common Honey Bee, and the society of Ants ; and the existence of a higher temperature than that of the atmosphere in the other families has only been inferred. Those species unto which I have devoted particular attention are the Bombus terrestris and Apis Mellifica. Bomhus terrestris. — 1. Temperature of Nests tinder observation. During the summer of 1830, having obtained a colony of this species, with the ori- ginal parent bee, from the neighbourhood of Richborough, near Sandwich, (which loca- lity had before that time afforded me opportunity of observing the habits of other species of this interesting family of insects,) I removed it from its locality in the earth to my own residence, the distance of a mile, and placed it in a small insect breeding cage for the purpose of more closely watching the economy of this species. The bees at first were somewhat irritable, and of course were kept in close confine- ment, and were fed with moistened sugar ; but within a day or two they became quite accustomed to their new residence, and I had ample opportunity of watching the economy of the nest. On the third day they were placed on a table in my sitting-room near the window, which remained open, and also the door of the cage, that the bees might go abroad and return at pleasure, which they did with as much regularity after the first day or two as if the nest had been placed in its proper locality in the earth. I had thus most ample opportunity of watching their habits. The nest consisted of from forty to fifty individuals, and it gave me great pleasure in being able to confirm many of the statements made respecting- these insects by Huber. During the time the bees were in my possession, a period of nearly three weeks, I observed upon introducing a thermometer among them, that the temperature of the nest varied at different times, and was considerably higher when they were in a state of excitement; but the circumstance did not then attract my particular attention. In the summer of 1 834, while engaged with the observations before detailed, I determined to repeat the observa- tion which I then remembered having made in 1830; and accordingly on the 10th of July 1834, having taken a nest of Bombus terrestris with brood comb, it was placed on a table near the window of my apartment, in a small box about eight inches square, and four deep, covered with green gauze, and after the first day’s confinement the bees were allowed to go and return as on the former occasion. Soon after com- mencing my observation, I was interested in observing that the bees were at first greatly affected and agitated by the slightest noise, such as the removal of a chair, or one’s footsteps about the room, or the passing of carriages along the road, which was at least thirty feet distant from the window of the apartment; but they were not in MR. NEWPORT ON THE TEMPERATURE OF INSECTS. 295 the slightest degree affected by persons talking loudly in the room, while a gentle tap with one’s finger on the table put them immediately into a state of the greatest agi- tation. Hence during the observations it was necessary to be cautious, and not disturb the bees when wishing to take the temperature of the nest. The bees, how- ever, in the course of a day or two became accustomed to their situation, and were not disturbed by slight noises or vibrations ; and I was then enabled to take their temperature under all circumstances. The observations were commenced at 12 a.m., July 10, about two hours after the bees were placed in the box. The temperature of the atmosphere was then 70°*5 Fahr., that of the box and nest 73° ; but when they be- came excited it soon rose to 77° but gradually subsided again to 73° as the bees became quiet. The thermometer was introduced very carefully under the gauze cover- ing, and was not allowed to touch the bodi es of the bees in this and the subsequent ob- servations. At 1^ p.m., the insects having remained at rest for more than a quarter of an hour, atmosphere 70°, the thermometer, introduced as before, rose to 75°, and in a few minutes afterwards, when the bees had become much excited, to 80o,2, a difference of 1 0o,2 between the temperature of the atmosphere and that of the box ; and when the body of a bee touched the bulb of the thermometer, even but for an instant, the mer- cury immediately rose at least a degree on the scale. At 2^, atmosphere 70°'5, bees quiet, atmosphere of the box 76° ; but when they became much excited it rose in four minutes to 80°*4. At 12^ midnight, atmosphere 68°*5, interior of the box was 73°, the bees having been quiet during the previous nine hours; but when they became greatly excited it rose to 80°'3, a difference of 1 1Q,8. At 6 o’clock on the following morning, July 11, atmosphere 67°, the interior of the box was 71°, but when the bees became much excited it rose to 77°'3. At 12| midnight, atmosphere 67°’5, box with bees at rest 73°, when agitated 78°. At 7 a.m., July 13, the box in which the bees were con- fined had remained closed during the night, which had been perfectly calm and still, and at the time of making the present observation there was not a breath of wind stirring; indeed the air was suffocatingly calm, and its temperature 68 0-7 ; when the thermometer was carefully introduced under the lid of the box the mercury rose to 72°, which was the temperature of the interior of the box around the nest, but when the thermometer was placed in the nest itself the temperature stood at 76°‘5. 2. Nest of Bomb us in its natural haunts. Having proceeded thus far with my observations on the temperature of the nest, removed from its proper locality in the earth for the purpose of experiment, it became a matter of interest to endeavour to ascertain its temperature while undisturbed in its natural haunts. Having at length discovered the nest of a species of Bombus nearly allied to Bombus terrestris situated in a shaded chalk bank near the ground, and about eight inches from the surface, at 10 a.m., — the temperature of the atmosphere in the shade four feet from the ground being 680,75 while that of the exterior of the chalk bank in which the nest was situated, and near the entrance to it was 66°, — I very carefully 296 MR. NEWPORT ON THE TEMPERATURE OF INSECTS. introduced a small thermometer without disturbing the inmates, and found that the temperature of the interior of the nest was 83°, but in a few minutes it rose to 85°; it was thus evident that the temperature of the nest upon which I had made the pre- ceding observations was at about its average temperature in its natural haunts. 3. Nurse Bees. — Voluntary Power of generating Heat. The above experiments on the nest of Bombus terrestris thus confirmed the results of my observations made a short time before on individual insects with regard to the rapid transmission of heat from the body of the animal when in a state of excitement, and also in a less degree when in a state of rest ; but during the time I was engaged upon them they also afforded me a new and totally unexpected phe- nomenon, and one which is not a little interesting and important as regards its con- nection with the origin of animal heat ; — it was the capability which these insects possess during the act of incubation on the cells which contain nymphs, of increasing their own temperature many degrees above that of the surrounding medium, of in fact a voluntary power of generating heat through means of respiration. Huber has stated that there are certain individuals in the nests of the Humble Bees, and among the bees in a hive, which at a particular season of the year are employed to impart warmth from their bodies to the young bees in the combs by brooding over them, and these he called Nurse Bees. It gives me great pleasure in being able to bear testimony to the correctness of his statement, particularly with regard to those in the nest of the Humble Bee, which I had ample opportunity of observing. These indi- viduals are chiefly the young female bees, and at the period of the hatching of nymphs they seem to be occupied almost solely in increasing the heat of the nest and com- municating warmth to the nymphs in the cells by crowding upon them and clinging to them very closely, during which time they respire very rapidly, and evidently are much excited. These bees begin to crowd upon the cells of the nymphs about ten or twelve hours before the nymph makes its appearance as a perfect bee. The incu- bation during this period is very assiduously persevered in by the Nurse Bee, who scarcely leaves the cell for a single minute ; when one bee has left another in genera! takes its place : previously to this period the incubation on the cell is performed only occasionally, but becomes more constantly attended to the nearer the hour of develop- ment. The manner in which the bee performs its office is by fixing itself upon the cell of the nymph, and beginning at first to respire very gradually ; in a short time its respiration becomes more and more frequent, until it sometimes respires at the rate of 120 or 130 in a minute. I have seen a bee upon the combs perseveringly continue to respire at this rate for eight or ten hours, at the expiration of which time its body has become of a very high temperature, and on attentive observation the insect is often found in a state of great perspiration ; when this is the case the bee generally discontinues her office for a time, and another individual will sometimes take her place. Very frequently the Nurse Bee respires with much less rapidity, and MR. NEWPORT ON THE TEMPERATURE OF INSECTS. 297 remains many hours on the cells. The very high temperature unto which the insects are able to raise their own bodies, and the cells upon which they are incubating at this period, will be best shown by detailing the continued observations on the nest. At 8 a.m., July 13, when the temperature of the atmosphere was 7l°'8, and the temperature of the interior of the box around the nest 72°‘5, I inserted the bulb of a fine thermometer very carefully between the abdomen of several bees and the cells upon which they were incubating, and which contained nymphs, and found the body of a single nursing bee was 84°* 1 , while the exterior of some cells that contained nymphs, but which were not covered, was 76'5. At 8^ the temperature of the out- side of the waxen cover, or top of the nest, was 77°'7, and that of the atmosphere 72°*5, while the interior of the nest, where the bulb of the thermometer was introduced among four bees which were nursing upon the cells, was 890,2. At 8f, atmosphere as before, when the thermometer was introduced among seven nursing bees at the same spot, three of which were large females, and the others males, which also assist in the process of incubating, the mercury of the thermometer rose to 90o,2 Fa hr. At 9 a.m., atmosphere still 7 20,5, the temperature of the same bees still incubating was 920,3, and of others incubating in another part of the same nest 910,5 ; at 9^, atmosphere 72°7, that of the bees still nursing was 91°. At 12 a.m. the observations were resumed : in the interval between the last observation and the present time there had been a gentle shower with light wind, and the atmosphere had sunk to 7Q0,2 ; the tempera- ture of the Nurse Bees on the cell was now 920,5. The thermometer was raised to this height within about ten minutes, and was maintained at that standard as long as the bulb of the instrument was allowed to remain in contact with the bodies of the insects, while the temperature of some of the adjoining cells beneath the same cover, but which were not covered by the bees, was maintained at only 80o,2. Within a quarter of an hour after these observations were made three large female bees were hatched from the cells upon which the seven bees had been incubating ; the temperature of the atmosphere was then 720-2, while that of the Nurse Bees, which had now desisted from incubating, and consequently were respiring less rapidly, had sunk to 85°. It was thus evident that the greatest amount of heat is generated by the Nurse Bees just before the young bees are liberated from the combs, at which period they require the greatest amount of invigorating heat. It is at this period also, as before noticed, that the young bee is most susceptible of diminished temperature; it is then exceedingly sleek, soft, and covered with moisture ; perspires profusely, and is highly sensitive of the slightest current of air. It crowds eagerly among the combs and among the other bees, and everywhere where there is the greatest warmth. In the course of a few hours it becomes a little stronger, and is less sensitive, and better able to bear a di- minished temperature. It then moves about with less circumspection, and its wings, which at first are soft and weak, and bent upon its trunk, become plain and straight. When the young bee first leaves its cell it is entirely of a whitish or pale grey colour, but within half an hour the black markings on the thorax become very distinct, 298 MR. NEWPORT ON THE TEMPERATURE OF INSECTS. although they retain a tinge of grey colour for a much longer period; the yellow bands on the body and thorax are at first quite white, and it is not until an hour or two has elapsed that the principal yellow band on the thorax begins at length to gain colour, while it is several hours before the yellow bands acquire their full shade or degree of colour. During all this time the bee continues in an enfeebled state and takes no part in the business of the nest, but seeks for itself the warmest place among the combs, and it is not until sometime after it has acquired its proper degree of colour that it becomes active like the other bees, and is able to maintain its own proper temperature. It is thus evident, that the same principle which has been shown by Dr. Edwards to prevail with regard to the young of some of the mammiferous animals, that they are unable for a certain period after birth to generate and maintain within themselves a proper amount of temperature, but require to be cherished by external warmth, regulates also the development of the individuals of this family of Hymenopterous insects, from their pupa or nymph to their perfect state, and further tends to prove to us how universal and simple are the great laws which regulate the continuance of animal life. It is a curious fact that these bees do not incubate on the cells which contain only larvae, the temperature of the atmosphere of the nest being sufficiently high for them in that condition ; consequently the larvae at an advanced period do not require so high a temperature before changing into nymphs as that which has just been shown to be required by the nymphs before coming forth as per- fect insects. This will be shown in some observations made on larvae in the nest now under examination, at the same time with those just described, and also with others which were made on nymphs. The temperature of the atmosphere being 7®°, some of the cells which were open and contained larvae were exposed in the nest, and the Nurse Bees therefore covered them lightly with dried grass, of which the nest of this species of Bombus is usually composed ; but when the temperature of the atmosphere a few hours afterwards had risen to 73°'5, most of the dried grass with which these cells had been covered was removed, and the larvae were more exposed ; the temperature of these cells and the larvae being 77°'4, while that of the cell of a nymph, with the Nurse Bee upon it, in another part of the nest was 92°, and subse- quently when four large females were nursing around it was 94°T, the temperature of the atmosphere being still 7 2°‘5. When there are no longer any nymphs which are soon to be developed into perfect insects the necessity for generating a larger amount of heat is diminished, and the Nurse Bees remain in a state of quietude ; the temperature of the nest is then much lower than when young bees are about to be produced. This was the case on the 14th of July; the atmosphere was then 69°, while that of the nest was in no part higher than 7 20,5 ; and even when the bulb of the thermometer was in contact with the bodies of several of the bees, the mercury scarcely rose to 73°*5, while at 12 o’clock on the preceding night, when the atmosphere was 68°, and several young bees were soon to come forth, the temperature of the box was 70°‘5, and that of some bees MR. NEWPORT ON THE TEMPERATURE OP INSECTS. 299 very moderately excited in the act of nursing 83c,2. It is not only at the moment when the young bee is about to come forth that the Nurse Bees produce a larger amount of heat ; they keep up the heat to a considerable amount for some time after the young bee is developed. At p.m., July 14, the bees were again incubating, the atmosphere 690-5 ; the cells immediately beneath the cover of the nest were 890,4. At 2 p.m., atmosphere 690,5, the same cells were 92°-2, at which time most of the bees were crowding around this part of the comb, from which at 6 p.m. several young ones came forth. At 3 p.m., atmosphere 69°'5, the temperature of a single bee nursing on these cells was 91°. At 5 p.m., atmosphere 73°*4, atmosphere of the box was 75°-3, and that of four bees nursing 94°*2 ; while at 1 1 p.m., five hours after the young bees had been developed from this part of the comb and when no bees were present, the temperature at the very same spot was only 68°, exactly that of the open atmosphere; but in another part of the nest where the bees were again nursing it stood at 83°. It was in this way that the nurse bees constantly raised their own temperature and that of the cells upon which they were incubating whenever new bees were to be produced. In order to prove that this great amount of heat resulted directly from the temperature of the nursing bee, I placed the bulb of a thermometer on the back of a single individual that was nursing on the upper surface of a comb that was exposed to the temperature of the atmosphere, 71°-6, when it rose to and was main- tained exposed as it was at 85°, while the temperature of the cell immediately after the bee had quitted it was 75°’ 3, and it was maintained at that temperature several minutes. In other observations I found that on one occasion, when the atmosphere was 720-5, a single female bee while nursing upon a single cell, from which a perfect insect was developed about eight hours afterwards, had a temperature of 920,3 : the bulb of the thermometer in this instance was placed upon the cell immediately beneath the abdomen of the bee, which was respiring at the rate of 120 per minute. In another observation, when the temperature of the atmosphere was still the same, 720,5, a single bee while nursing had a temperature of 94°'5, but a little while after- wards when the atmosphere was 72°’7 it had subsided to 91°. These facts distinctly prove that bees have a voluntary power of evolving heat, while it seems only fair to conclude, on comparing the facts, that the quantity of heat produced in a given time and space, has relation to the number of respirations per- formed by the individual ; and from the quantity of atmospheric air consumed, and of carbonic acid gas evolved, that animal heat is greatly and perhaps almost entirely dependent upon the chemical changes which take place in the air respired. Temperature of the Hive Bee, Apis mellifica, Linn., during the Winter. The many curious facts connected with the production of heat in the Humble Bee and other insects, naturally disposed me to wish to extend my inquiries to the ascer- tainment of that of the inhabitants of the hive, and fortunately circumstances enabled me to carry my wishes into execution, and commence my observations in the summer mdcccxxxvii. 2 R 300 MR. NEWPORT ON THE TEMPERATURE OF INSECTS. of 1835. They were continued almost uninterruptedly until the spring of the present year. I had long doubted the statements of naturalists that the Hive Bee does not hybernate, but maintains a very high temperature in its dwelling throughout the whole winter. This statement is so at variance with everything that is known with regard to the habits of insects in this country,, especially those of the same class, the Humble Bees, that were it really the case it could not fail to be looked upon as quite anomalous in the economy of British insects. Swammerdam, Reaumur, and Huber were all of opinion that the Hive Bee does not at all enter into a state of hybernation, but continues active during the winter. Huber states expressly*, that so far from bees becoming torpid in winter, the temperature of a populous hive ranges from 86° to 88° Fahr. when the thermometer in the open air is several degrees below freezing. But these authors have been deceived with regard to the real fact. The Hive Bee certainly does not become torpid, but if entirely undisturbed it passes into that con- dition in which its temperature of body and quantity of respiration are very greatly diminished ; — a state of deep sleep in the combs, but a sleep which, so far from being continued at a very low atmospheric temperature, then becomes broken, and is only continued at a moderate temperature. It is true that when the hive is disturbed in the winter, and it becomes so very readily, its temperature is soon raised to a great height. There can be no doubt but that this was the case in the observations made by the authors just noticed. They must necessarily have disturbed the bees when they introduced the thermometer to take the temperature of the hive, since, as I am about to prove, there are periods during the winter when the temperature of the hive is so greatly reduced, and the bees are so inactive, that the temperature is scarcely above that of the open atmosphere ; and when the temperature of the air is increased rapidly, that of the hive is even below it for a short period, just as we saw in the ob- servations on the temperature of larvae during sleep ; but if at that very period the hive become disturbed, its temperature is raised in the course of a few minutes by the excitement of the bees to a very great amount above that of the atmosphere, as shown in Table XVI. Nos. 204, 205, so that we may fairly conclude that Huber and the other naturalists were deceived in their observations by arousing the bees while introducing the thermometer. The observations detailed in the accompanying Tables on the hive were commenced in October, when only a very few bees venture abroad, and were continued with but few intermissions to the end of September in the following year, when the bees are becoming inactive, and the temperature of the hive is very much reduced. All my observations on the Hive Bee were confirmatory of the conclusions deduced from observations on other insects, and proved that this useful and interesting little spe- cies does not form an exception to the general rule. From previous observations on the temperature of insects I had found that the * New Observations on the Natural History of Bees, by F. Huber. (Translation.) Third Edition. Edin- burgh, 1821, p. 224. MR. NEWPORT ON THE TEMPERATURE OF INSECTS. 301 amount of heat developed in a given time was in proportion to the quantity and ac- tivity of respiration, and that the temperature of each species of insect can only be increased to a certain extent above the temperature of the medium in which it is living, and that when it has arrived at that point, whatever it happens to be, a copious cutaneous transpiration takes place ; and if the temperature be still increased, the body of the insect becomes bathed in perspiration, and its temperature is immedi- ately begun to be reduced. Now the degree unto which the temperature of insects may be increased above that of the medium in which they are living, varies in the different species as well as in the different genera of insects ; each species has a cer- tain standard of its own, beyond which its increase of temperature cannot be carried. In some insects, as in the Hive Bee, this may perhaps amount to from fifteen to twenty degrees, while in others it perhaps scarcely exceeds one or two degrees above the temperature of the surrounding medium. Besides this, it has been found that insects have a power of generating heat when confined in a given space, and that this power is in proportion to the activity of respiration. I have had numerous proofs of this fact in my observations on the varying temperature of the hive. My experiments on the hive were conducted in the following manner: a common straw hive was placed with its entrance hole in the direction of another wooden hive, which was standing beside it in a bee-house, which was so constructed that the whole of the back part of the house could be removed or closed at pleasure. The proper entrance for the bees at the front of the bee-house was directly into the wooden hive, from the side of which there was a little covered communication with the entrance hole of the straw hive, to serve as a passage for the bees and a connection between the wooden and straw hive. The object of this was to prevent any sudden effect upon the temperature of the hive by changes which might occur in the temperature of the air without. The interior of the straw hive was thus subjected as little as pos- sible to the variations in the open atmosphere, since the bees were obliged to pass through the empty wooden hive to its entrance hole before they could reach the open air. In order to make the experiment with the greatest accuracy, it was necessary that the bees should never be disturbed while making an observation, and therefore a small crow-quill sized thermometer, with a long free bulb, was passed through a hole just large enough to admit it in the top of the straw hive, about eight inches from the centre, and retained there during the whole of my subsequent observations without being removed or touched. The bees at first seemed a little inconvenienced by its presence, but within two or three days they became accustomed to it, and, as I had reason to believe, removed the comb and wax from around it, so that the bulb of the instrument was remaining about an inch within the free space of the hive, and the observations were then made at intervals, and with the greatest accuracy. The temperature of the atmosphere was taken with a thermometer of similar size and con- struction to the one used for the hive, and the two had been carefully compared be- fore the first was passed into the hive. It was thus only necessary to notice from 2 r 2 302 MR. NEWPORT ON THE TEMPERATURE OF INSECTS. time to time the rise hnd fall of each thermometer, and to note the difference between them, the temperature of the air being of course taken in the immediate vicinity of the bee-house. By this course of observation it was found that the temperature of the hive, when the bees are in a state of repose, varies with that of the atmosphere, but that the change within the hive is never so rapid as in the atmosphere, unless the bees have been disturbed. When the temperature of the atmosphere has risen very suddenly, I have found it exceed that of the hive by one or two degrees, as in Table XVI. No. 1/3, provided the bees continue in a state of entire rest ; but if, on the contrary, the temperature of the atmosphere be suddenly diminished, that of the hive will sub- side also, but with much less rapidity. These facts are shown in the observations, Table XIV. Nos. 85 and 86, and also in all the observations on the tables which were made after one o’clock at noon on each day during the winter. Sometimes the ther- mometers became exactly equal to each other, as in No. 124. On the other hand, when the bees are in a state of activity and respiring quickly, the hive is even then affected in the winter months by great changes in the temperature of the external atmosphere, particularly if these changes occur late in the autumn or in the beginning of the winter season. But a change in the temperature of the atmosphere in summer does not so readily affect the temperature of the hive, because in summer, when the general temperature of the atmosphere ranges from 45° Fahr. upwards, the bees are always in a state of activity, and are not themselves so readily affected by sudden atmospheric changes of temperature ; while in winter, when the temperature of the season ranges from 45° Fahr. downwards, the bees are very soon affected by dimi- nished heat, and become disposed to pass into a state of hybernation, in which state, as we have before shown, scarcely any respiration takes place, and the temperature of the little animals sinks down, or very nearly so, to the temperature of the medium in which they are placed ; and if there be a direct and free communication between that medium and the external atmosphere, even down to that also. The amount of temperature in the individual bee I have been led to believe, as before stated, is in general from 10° to 15° Fahr. above the temperature of the medium in which it is living, when in a state of moderate excitement, but it seems liable to be still further increased at certain periods, as in the hive a short time before swarming, and when clustering together on the alighting board of the hive a short time before the colony departs. In some observations made on the 5th and 27th of June, when the temperature of the atmosphere ranged only from 56° to 58° Fahr., the temperature of the hive was 96° and 98°, being at least 40° above that of the atmosphere. Now the occurrence of this amazingly high temperature at these periods is readily ex- plained by what we have learned of the habits of bees in incubating on the combs,, and voluntarily increasing their heat, by means of respiration, before the new bees come forth, that being the season in which the population of the hive is perhaps doubled within a very few days. A similar explanation is also afforded to us, i. e. the excitement of the insects, and consequent greatly increased quantity and activity MR. NEWPORT ON THE TEMPERATURE OF INSECTS. 303 of their respiration, — of the surprising amount of temperature that may suddenly be developed in the hive, even in the midst of winter, when the bees are disturbed, as in the observations 190, 193, 195, 205, 214, 221, and many others on these tables. I have found that be the insects ever so quietly at rest, and even passing into a state of hybernating sleep, and although the temperature of the atmosphere be very much reduced, as in the observations just noticed, and also in Nos. 52, 134, 137, and 139, yet by exciting and arousing them, by gently tapping and shaking the hive, the bees are immediately put into a state of great agitation, and in less than ten or fifteen mi- nutes the mercury will be raised on the scale of the thermometer upwards of 30° Fahr. above the temperature of the hive immediately preceding the experiment, when the bees were quiet, although the temperature of the atmosphere may scarcely exceed 35° Fahr., and although the temperature of the hive itself had previously been not more than 6° above that of the atmosphere. But this is not the greatest difference I have observed between the temperature of the excited hive and that of the atmosphere. It may appear surprising that any part of a well-peopled hive should at any time have a temperature lower than that of freezing, 32° Fahr., yet I have occasionally found this to be the case both during the last winter, 1836-37, and once in the preceding of 1835-36. In the latter instance it occurred but once, as indicated by the thermo- meter. This was in the hive upon which I have made the whole of my series of ob- servations, and the hive at the time was well populated. It happened on the morning of January 2, 1836, at a quarter past seven, just before sunrise, when there was a clear intense frost, and the thermometer stood at 17°'5 Fahr. The bees were per- fectly quiet, and the thermometer which had been untouched since its first introduc- tion into the hive stood at 30°, or only 120,5 above that of the atmosphere. The bees were then aroused in the usual manner by tapping the exterior of the hive, and in sixteen minutes the mercury of the thermometer had risen to 70° Fahr., but I was unable to excite the hive sufficiently to increase the temperature beyond this standard. This was 52° Fahr. above that of the external atmosphere, and 40° Fahr. above the previous temperature of the hive at that spot ; but this was only the apparent, and not the real temperature of the hive, and resulted from the great accumulation of ex- cited bees in the immediate vicinity of the bulb of the thermometer, within the hive, because a second thermometer having been introduced at a corresponding part of the top of the hive, at about five inches’ distance from the first, indicated a temperature in that part of only 45° Fahr. These observations were sufficient to prove the incor- rectness of attempting to ascertain the temperature of a hive of bees by occasionallv introducing a thermometer among them and taking the temperature of the bees when excited by its presence. This circumstance was not lost sight of in my subsequent observations. At 12 a.m. on the same day the temperature of the atmosphere had risen to 30o,7 Fahr., while that of the hive, as indicated by the first thermometer, had subsided to 46° Fahr., and the bees within had become perfectly quiet. On the 5th of January at 1 p.m., the temperature of the atmosphere having risen to 50° Fahr., 304 MR. NEWPORT ON THE TEMPERATURE OF INSECTS. that of the hive stood only at 55° Fahr., while the bees aroused by the suddenly in- creased temperature of the atmosphere were becoming- active ; and when the hive was again excited by tapping it for a few minutes, the thermometer rose to 820-2, a dif- ference of 32° above that of the atmosphere, and 2 7° above that of the previous tem- perature of the hive, after which the temperature of the hive was maintained at 78° during several hours, while the bees continued in a state of activity, the temperature of the atmosphere being then congenial to their habits, and equal to the average temperature of the month of April, when the hive is again becoming active. But these are not the greatest amounts of temperature observed in the hive on its be- coming excited during winter. In a second straw hive, which was exposed like the usual cottage hives to the open air, I found the interior temperature, at 10 a.m., on the 2nd of February, after the hive had been disturbed by tapping on its exterior, raised to 102° Fahr., the temperature of the atmosphere being 34°*5, a difference of 67°‘5, while the first hive, which had not been disturbed, was then 48°*5, a difference of only 14° Fahr. between it and the surrounding atmosphere. Although the hive be very much disturbed and its temperature be greatly increased by exciting the bees during the middle of winter, it will soon become quiet, and its temperature be reduced again to within ten or twelve degrees of the temperature of the atmosphere within ten hours, as in the observations No. 205 and following, made on the 2nd of January. When the temperature of the hive has been increased suddenly, during the earlier or latter part of the winter, which we have just seen is the case when the hive is disturbed, the sudden increase of heat in their dwelling becomes intolerable to the little inhabitants, and they immediately endeavour to reduce it by ventilation, pro- vided the temperature of the external atmosphere be not too low to endanger them, by exposing themselves at the entrance of the hive. When the temperature of the atmosphere is at or near 40° Fahr., at the time when the hive is disturbed the heat soon becomes oppressive, and although the degree of excitement within the hive be very great, its temperature is quickly moderated by the assiduity of the bees. I have often been amused by observing them, after the hive has been disturbed for a short time, although but a few minutes before there was not a single bee on the alighting board, come hastily to the entrance of the hive, and having arranged themselves within three fourths of an inch of the doorway, begin to fan with their wings most laboriously, to occasion a current of cool air through the interior of the hive. This act is the more assiduously performed, when, as in the hive under observation, there is not a free communication between the interior of the hive and the open atmosphere. On one occasion, No. 138, when the temperature of the hive had been raised to about 70° Fahr., the external atmosphere being scarcely more than 40° Fahr., the bees at midday maintained the temperature of the hive steadily at 57° by this mode of ven- tilating, the hive still continuing excited. Although the bee can bear the transition from a hot to a cool atmosphere without MR. NEWPORT ON THE TEMPERATURE OF INSECTS. 305 inconvenience during the spring when the temperature of the atmosphere is only 45° Fahr., yet it cannot bear a sudden transition from hot to cold in the winter, even when the temperature of the atmosphere is at 40° Fahr. I had a striking proof of this while making the above observation, No. 138, at 11 a.m., on the 14th of November. The hive had been for a considerable time in a state of excitement, and its apparent temperature was raised to nearly 70°, while a great many bees were ventilating at the entrance, and others flew abroad into the open air while the sun was shining, but they very soon returned to the hive again. Shortly after this I found one individual lying within the entrance of the wooden hive apparently dead. On exposing it for a few minutes to the sun it began to revive, and was completely recovered, and able to fly again to the entrance of the hive, in six minutes. A thermometer placed close to the torpid bee in the sun rose only to 53°*5 Fahr. It was thus shown that the bee cannot bear a sudden transition in winter from a high to a low temperature, yet it will be seen by the Tables at Nos. 116 and 133, that the bees were active when the tem- perature of the hive was not higher than 43°, that of the atmosphere being 35° Fahr., so that it is not until the medium in which the bees are residing is below 40°, that the insects begin to pass into a state of repose. From a gradually increased temperature through the months of March and April, the hive acquires its maximum amount of temperature in the months of May and June, the periods of the greatest activity, and when the largest proportion of young- bees is produced. We are now aware of the circumstances connected with the great amount of temperature in the hive at this season, and of the power which the bees themselves possess of increasing it at pleasure, or as the necessity for imparting it to the young may demand. These facts will explain a circumstance connected with the temperature of the hive, which without a previous knowledge of them might have been of difficult solution. It is the circumstance before alluded to of one part of the hive being of a higher temperature than another. This is the case in the hive even when the bees are not in a state of excitement. I had been led to the observa- tion of this fact during the winter when making experiments on the bees in a state of excitement. Being anxious to know whether this was also the case in the spring and summer, I introduced another thermometer through the top of the straw hive, at the same distance from the centre, but on the side opposite to the one previously in- serted. This was on the evening of the 12th of May, when the temperature of the atmosphere was 58° Fahr. The instrument on passing through the top of the hive was plunged into a cell of honey, and the mercury rose to 78° Fahr., which of course indicated the real temperature at that time of the honey and interior of the hive. The mercury in the first or original thermometer was very quickly raised to 90° Fahr. in consequence of the excitement of the bees within the hive, but shortly afterwards sunk to 84°. During this time the temperature of the opposite side of the hive, as indi- cated by the newly introduced thermometer, rose to and remained at 79° Fahr. Here then we have a clear proof that the sudden increase of temperature when a thermometer 306 MR. NEWPORT ON THE TEMPERATURE OF INSECTS. is passed into the hive arises from the bees flocking around it, and it is also a proof that the natural temperature of these insects in a state of excitement may be raised to 20° Fahr. above that of the medium in which they are living, as shown in the ob- servations on the Humble Bees. But this variation in the amount of temperature in different parts of the hive does not very much affect our means of judging of the average amount of the temperature of the hive at different periods when the thermo- meter remains entirely undisturbed, because it is found that when the temperature of the air is examined at about the same hour of the day, on two or more success- ive days, and all other circumstances being nearly the same, there will be but little variation in the average amount of temperature ; so that we find the temperature of the hive, at the period of swarming, amounts to about 96° Fahr., while in the month of August it is seldom more than 80° Fahr., or perhaps 86°, even in the middle of the day, when the temperature of the atmosphere is often more than 78° Fahr. The cause of this difference between the amount of heat in the hive at this period and in the time of swarming is readily explained by reference to the facts connected with the production of heat. Less heat is in reality produced from the same volume of air consumed at the high temperature of 78° Fahr. than when the atmosphere is not more than 66° Fahr., as is often the case at the period of swarming, while in reality a far less volume of air is consumed in August than in May, because the bees are not in the same state of excitement. These facts readily account for the diminished tem- perature of the hive in the month of August, when the temperature of the atmosphere is in general higher than when the bees are most active. During the period of swarming in 1 836 1 availed myself of the opportunity afforded me by the annular eclipse of the sun on the afternoon of the 15th of May, of watch- ing the effect of diminished light and atmospheric temperature on the temperature of my hives, and the activity of their inhabitants, and found, as shown in the accom- panying Table, that in proportion to the diminution of light the hives became quiet, and the temperature of the hives decreased until after the eclipse had passed its maximum, when as the light began again to increase, the activity of the hives became restored, and with it a considerable increase of heat. MR. NEWPORT ON THE TEMPERATURE OF INSECTS. 307 Table VII. Showing the variation in the Temperature of two Bee-hives compared with the Tem- perature of the atmosphere, as observed at Chichester, in Sussex, during the An- nular Eclipse of the Sun on the afternoon of May 15, 1836. d X W Period of ■d c o o d d o C4 o £ % O CtJ Increase in Grains. Age. Remarks. 1834. h , 1 Sphinx ligustri (larva) ... July 30. a.m. 8 70 J J ust entered its fifth and last ( skin. 2 Sphinx ligustri (larva) ... P.M. 4 74-6 75-5 •9 151 J Quiet; has voided no faeces for 3 Sphinx ligustri (larva) ... 31. P.M. 4 19-9 0 4*8 \ 10) hours. 4 Sphinx ligustri (larva) ... Aug. 1. P.M. 4 27-4 7-5 3 da"* TT , 5 Sphinx ligustri (larva) ... 2. P.M. 7 73-8 •2 •4 41-3 6-5 13-9 4 days Sleeping. 6 Sphinx ligustri (larva) ... 3. P.M. 4 15 72-4 73-4 1- 50 56-6 8-6 15-3 5 days Quiet. 7 Sphinx ligustri (larva) ... 4. P.M. 5 71-9 72-9 1* 50 69-1 19 13-5 6 days Quiet, but not feeding. 8 Sphinx ligustri (larva) ... P.M. 5 45 72-5 73-8 1-3 56 71-5 9 Sphinx ligustri (larva) ... 5. A.M. 9 71-3 72-6 1*3 51 77-5 1 1-4 6 7 days Aroused and beginning to feed. 10 Sphinx ligustri (larva) ... P.M. 8 30 69-9 711 1-2 51 85 10-8 7-5 Just aroused. 11 Sphinx ligustri (larva) ... 6. A.M. 7 30 711 72-3 1-2 50 90-5 16-9 5-5 8 days Aroused; beginning to feed. 12 Sphinx ligustri (larva) ... P.M. 5 30 70 71-2 1-2 47 93 12-5 3-5 Feeding. 13 Sphinx ligustri (larva) ... 7. A.M. 6 68-3 68-7 •4 36 98-8 14 5-8 9 days Sleeping. 14 Sphinx ligustri (larva) ... A.M. 6 15 68-4 69-3 •9 42 98-8 15 Sphinx ligustri (larva) ... P.M. 4 30 69-2 70-3 11 43 100-1 12-6 1-3 Quiet ; feeding. 16 Sphinx ligustri (larva) ... 8. P.M. 3 30 72 72-9 •9 42 92-1 23 10 days f Very active ; discoloured ; re- fuses food. 17 Sphinx ligustri (larva) ... P.M. 5 30 71-3 721 •8 40 91-9 J Active ; more discoloured ; 18 Sphinx ligustri (larva) ... P.M. 6 30 71*5 72-3 •8 40 91-7 1 pulse laborious. 19 Sphinx ligustri (larva) ... P.M. 7 30 70-4 71-4 1* 40 91-5 [Much excited; fasting; no ( faeces passed. 20 Sphinx ligustri (larva) ... p.m. 10 30 68-3 69-1 •8 37 90 •9 j Active ; more discoloured ; 21 Sphinx ligustri (larva) ... 9. A.M. 7 30 67-4 67-8 •4 24 88-7 11 days 1 voided soft discoloured faeces. Has slept during several hours. 22 Sphinx ligustri (larva) ... A.M. 7 45 68-5 69-1 •6 28 88-6 / Awaking; temperature of air 1 rising rapidly. 23 Sphinx ligustri (larva) ... P.M. 11 30 68-3 68-8 •5 29 80-3 fin incessant action; about to f enter the earth. This difference in the velocity of the circulation at certain periods is an important circumstance as connected with the present subject, — the relation of the velocity of circulation to the temperature and respiration of the insect. For the purpose of ascertaining the rate of pulsation at different periods of the larva state with precision, I selected a healthy specimen of Sphinx ligustri, and commenced my observations upon it exactly seventy hours after it had left the ovum. At the moment of leaving the ovum it weighed only one eightieth part of a grain, but I was accidentally pre- vented from watching the rate of pulsation at that time. This individual was kept apart from other specimens from the moment it escaped from the egg until it changed into the pupa state. During this time, its weight, faecal expenditure, rate of increase from the making of one observation to the making of another, were all carefully noted, as well as the velocity of the circulation at different periods of its growth. Unfortunately, however, I was then without my thermometers, which prevented me from observing the temperature of the insect, and thereby completing the exami- nations. From these observations it appeared that the rate of pulsation is greatest 314 MR. NEWPORT ON THE TEMPERATURE OF INSECTS. (luring- the first and second periods of the larva state, or before it has entered its third skin, and when its weight is no more at most than two thirds of a grain. From not knowing the temperature of the atmosphere at the period of making the observations on this insect in its second skin, I am doubtful whether the rate of pulsation be not in reality greatest during the earlier life of the larva, before it has thrown off its first skin, because this was really the case in all the observations, if we except only two which were made on the afternoon of the same day, when the larva was at about the age of two hundred and seventeen hours. These observations being excepted, it will be seen from Table IX. that the rate of pulsation is gradually diminished from the earliest period of the larva state until the insect has changed into a pupa, — that while the rate of pulsation within % few hours after the insect has left the egg varies from seventy- five to ninety, and in its second skin, or at an average age of about two hun- dred and forty hours, it is but very little lower, it becomes in its third reduced to an average of seventy-five, in its fourth to less than sixty, in the middle period of its fifth to a maximum of fifty-five, and the latter period of the same to scarcely more than thirty-two pulsations per minute. These are interesting facts as connected with the power which the insect possesses of generating heat. It is, as before stated, at about the middle period of its fifth state or condition as a larva, when it is feeding most voraciously, that the insect is able to generate the greatest amount of heat. Although it will be seen from the additional facts about to be stated that both during sleeping and activity, when most vigorous as a larva, as also when passing into the enfeebled condition of a pupa, there is a coincident and correspondent activity or diminution in the rate of pulsation with the increase of motion, respiration, or diges- tion ; yet the primary source of the development of heat is not dependent upon the velocity or rapidity of the circulation, since the period in which there is the greatest rapidity of circulation is that in which the larva is least able to generate and maintain its greatest amount of temperature. Another circumstance which tends greatly to prove that the amount of heat does not necessarily depend upon the rapidity of the circulation is the different rates of pulsation when the insect is placed in different tem- peratures, or when in different states of health in the same temperature. In the first case the rate of pulsation may be very considerably increased, while the amount of tem- perature remains nearly, or perhaps exactly the same. In the latter instance the tempe- rature may continue exactly the same, but the rate of pulsation be diminished. Thus in two specimens of Sphinx ligustri which were both of the same age, and in similar conditions of activity, feeding in the same atmospheric temperature, when the obser- vations were made upon both at the same time, the temperature of the insects was exactly the same, '9 above that, of the atmosphere, but the rate of pulsation in one specimen, which was perfectly healthy, was forty-one beats per minute ; while in the other, which was unhealthy, it was only thirty-eight. MR. NEWPORT ON THE TEMPERATURE OF INSECTS. 315 Table IX. A Table showing the rate of Pulsation of the Dorsal Vessel at different periods of the Larva and Pupa state of the Sphinx ligustri, Linn. i - Species. 1 2 3 ■i 5 o 7 s 9 10 j i 12 13 n 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 Sphinx ligustri (larva). Sphinx ligustri (larva). Sphinx ligustri (larva). Sphinx ligustri (larva). Sphinx ligustri (larva). Sphinx ligustri (larva). Sphinx ligustri (larva). Sphinx ligustri (larva). Sphinx ligustri (larva). Sphinx ligustri (larva)., Sphinx ligustri (larva)., Sphinx ligustri (larva).. Sphinx ligustri (larva).. Sphinx ligustri (larva).. Sphinx ligustri (larva).. Sphinx ligustri (larva).. Sphinx ligustri (larva).. Sphinx ligustri (larva).. Sphinx ligustri (larva).. Sphinx ligustri (larva).. Sphinx ligustri (larva).. S ,hinx ligustri (larva).. Sphinx ligustri (larva).. Sphinx ligustri (larva).. Sphinx ligustri (larva).. Sphinx ligustri (larva).. Sphinx ligustri (larva).. Sphinx ligustri (larva).. Sphinx ligustri (larva).. Sphinx ligustri (larva).. Sphinx ligustri (larva).., Sphinx ligustri (larva)... Sphinx ligustri (larva)... Sphinx ligustri (larva)... Sphinx ligustri (larva)... Sphinx ligustri (larva)... Sphinx ligustri (larva)... Sphinx ligustri (larva)... Sphinx ligustri (larva)... Sphinx ligustri (larva)... Sphinx ligustri (larva)... Sphinx ligustri (larva)... Sphinx ligustri (larva)... Sphinx ligustri (larva)... Sphinx ligustri (larva)... Sphinx ligustri (larva)... Sphinx ligustri (larva)... Sphinx ligustri (larva)... Sphinx ligustri (larva)... Sphinx ligustri (larva)... Sphinx ligustri (larva)... Sphinx ligustri (larva)... Sphinx ligustri (larva)... Sphinx ligustri (larva)... Sphinx ligustri (larva)... Sphinx ligustri (larva)... Sphinx ligustri (larva)... Sphinx ligustri (larva)... Sphinx ligustri (larva)... Sphinx ligustri (larva)... Sphinx ligustri (larva)... Sphinx ligustri (larva)... Sphinx ligustri (larva)... Sphinx ligustri (pupa)... Period of obser- vation. 1835. July 14 p.m. 2 15 16 p.m. 5 17 A.M. 12 18 p.m. 2 19 p.m. 2 P.M. 4 20 p.m. 2 21 p.m. 2. 22 a.m. 12 P.M. 3; 23 A.M. P.M. P.M. 24 p.m. 25 A.M. 26 A.M. A.M. 12 27 28 A.M. 7 P.M. 1 29 a.m. 7 A.M. 10 Aug. 30 p.m. P.M. 31 P.M. 1 P.M. P.M. 2 a.m. 1 1 1 P.M. 3i P.M. 6j 3 A.M. 7 P.M. If 4 A.M. 12 5 p.m. 5 P.M. 10 4 6 A.M. 12 7 A.M. 7 1 P.M. 7| 8 A.M. 8f P.M. li P.M. 10 9 A.M. 6-J A.M. Hi A.M. 12 P.M. 54 10 A.M. P.M. P.M. 1 1 A.M. P.M. P.M. 12 A.M. A.M. 12 P.M. 1 i P.M. 13 A.M. P.M. 14 A.M. P.M. 15 A.M. A.M. 124 P.M. 5 9-4 64 4 74 9 80 73 108 103 85 87 79 20 A.M. 10 34 39 38 37 41 47 39 28 36 55 43 29 53 46 29 50 45 44 52 52 47 33 34 28 36 34 31 26 22 •04 •05 •25 Age in days or hours. 1 day •02 1- 9 2- 3 3-5 OY> 5-9 9-4 10-5 13- 4 14- 7 15- 1 18- 3 19 - 7 17-1 19-7 27 -7 33-3 40-2 42-6 49-1 54 58- 1 59- 1 63-6 72-7 83-5 86-7 90-2 102 106-6 118-2 117- 4 116-7 123 114-4 123- 3 124- 7 118- 2 100-1 97-2 •2 1- 4 2- •5 1-6 •7 •6 2-4 1-1 1-0 •4 1-2 711 •7 1-6 5- 3-1 3- 8 2-7 4 2 5- 2-75 0 5-6 8-3 4- 9 8-9 13 8- 7 9- 6 19-3 18-7 2-2 13 0 10-4 17-2 4-7 0 0 2- 4 3- 5 1-1 2- 9 1-3 •4 3- 2 1-4 Skin. 3-2 0 2-6 8- 5- 6 6- 9 2- 4 6-5 4-9 4-1 1 4-5 9-1 10-8 3- 2 3- 5 11-8 4- 6 11-6 0 0 6-3 0 8-9 1-4 0 0 0 2-6 8-6 6-5 18-1 2-9 3 days, or 51 4 days, or 70 5 days, or 96 6 days, or 1 20 122 7 days, or 144 8 days, or 168) 9 days, or 190 193 10 days, or 2094 215 217 11 days, or 241 4 12 days, or 25 9 £ 13 days, or 282 286 14 days 15 days, or 329 335 16 days, or 3534 356 17 days, or 383 3894 18 days, or 412 19 days, or 4334 4394 20 days, or 453^ 4574 4604 21 days, or 473 479f 22 days, or 502 23 days, or 531 5364 24 days, or 550 25 days, or 5694 581f 26 days, or 594J 5994 620 27 days, or 6284 6334 634 6394 28 days, or 653 6594 665 29 days, or 677 6844 6894 30 days, or 7014 706 7074 725^ 31 days, or 7244 734 32 days, or 7494 755s 33 days, or 775 7784 783 Remarks. 28-1 38 days, or 903 Larva has just burst from the egg. After leaving the egg. Quigt, but not sleeping. A little excited. Has been perfectly at rest for an hour. Sleeping. Sleeping, preparing for change. Has just assumed its second skin. Sleeping, but has not yet eaten. Quiet, but not sleeping. Sleeping. Quiet, but not sleeping. Sleeping. Sleeping, and preparing for change. Has just assumed its third skin. Sleeping. Feeding, atmospheric temperature reduced Sleeping. Quiet, but not sleeping. Sleeping, preparing for change. Has just assumed its fourth skin. Sleeping, has fed a little. Sleeping. Sleeping. Sleeping. Sleeping. Sleeping. Quiet, but not sleeping. Sleeping. S'eeping. Has been sleeping 12 hours for changing. Has just assumed its Jifth skin. Sleeping. Sleeping. Sleeping, pulse irregular. Quiet. Quiet, pulse full and quick. Feeding. Sleeping. Perfectly at rest, and sleeping. At rest. Feeding. Sleeping. Sleeping. Sleeping. Sleeping. Sleeping. Sleeping. Feeding. Feeding. Feeding. Has been feeding during the last hour. Quiet. Has escaped unfed during the night. Quiet. Sleeping. Active, and discoloured for change. Very active, preparing for change. Restless, discoloured. Just entered the earth for changing. Pupa still soft, has very recently changed. 2 T MDCCCXXXVIJ. 316 MR. NEWPORT ON THE TEMPERATURE OF INSECTS. Thus also in the larva of the Puss Moth, Table X. A. No. 7 to 27. Although the temperature of the atmosphere was gradually raised through twelve successive hours from 690,5 Fahr. at 5f a.m., — when the larva, which had been sleeping through several hours, and had a temperature of only 0,5 above that of the atmosphere, and its pulse was beating at the rate of forty-seven per minute, — to 80o,4 Fahr. at p.m. the insect then had a temperature of only °-8, while its pulse was beating at the rate of eighty-eight per minute. Again, at 7 on the following morning, atmosphere 7o°‘ 2 Fahr., the temperature of the insect at rest was only°9 ; at the expiration of one hour and a half it had not been increased, and the insect was still at rest, but the pulse had risen to sixty-eight, while at 9 a.m., when the insect was aroused and feeding, its amount of temperature was still the same, but the number of its pulsations then amounted to seventy-two. At 7 o’clock on the following morning, when the insect was active and preparing for transformation, its temperature being °‘7, its pulsations were at the rate of sixty per minute ; but half an hour afterwards, when the tempe- rature of the insect was 0,9, the number of pulsations was not increased ; and at the expiration of an hour, when the temperature had again sunk to °‘7, the pulse had also subsided to fifty-four. This very insect, A. No. 1, which immediately after it was cap- tured had been placed in a box in my coat-pocket, and after remaining there for some time, excited by immoderate warmth, had a temperature of 130,5 Fahr. above that of the atmosphere, which was then 68° Fahr., while the pulse of the insect was ninety- nine per minute. But one hour afterwards, when its temperature had sunk to 20,3, the pulsations were only sixty-four. At the expiration of another quarter of an hour they had risen again to seventy-two, while the temperature of the insect had sunk to 10,6 Fahr. Thus then, although in general we cannot fail to observe the almost con- stant uniformity or correspondence between the number of pulsations and the tempe- rature of the insect, as in Nos. 6, 14 and 17, it is evident that the amount of tempe- rature does not necessarily depend upon the rate or mere velocity of pulsation. On examining the Table now referred to it will be seen that there is a remarkable difference in the rate of pulsation, as well as in the temperature of the larva of the Puss Moth and of the Sphinx ligustri of the same age, and at about the same tempe- rature of the atmosphere as on Tables VIII. and X., from which it is seen that neither the temperature of body nor the rate of pulsation is so great in the Sphinx as in the Puss Moth, while in both is observed the general coincidence of the rate of pulsation with the amount of temperature. In both the Tables VIII. and IX. it is seen that when the larva is about to change into the pupa state the pulsations are reduced from thirty-two to twenty-eight, and even to twenty-six ; and when the change into the pupa state is completed, the rate of pulsation is not more, in some instances, than twelve beats per minute. When the insect is in its most complete state of hyberna- tion the circulation in the pupa is reduced to its lowest condition, and there is perhaps an almost entire absence of pulsation, although I have reason to believe that the fluids still circulate even when there is no development of external heat. MR. NEWPORT ON THE TEMPERATURE OF INSECTS. 317 Table X. Showing that the Temperature is greater and the Pulsation more frequent in the larvm of those insects which undergo their metamorphoses in the open air, as the Puss Moth ( Centra vinula), than in those which undergo their ciianges in the earth, as the Sphinx ligustri , and others. No. of Exp. Species. Period of observation. Atmo- sphere. Insect. Difference. Pulsation, | to 1834. h m i Cerura vinula (larva), A. July 16 a.m. 9 68 81-5 13-5 99 7th day. 2 Cerura vinula (larva), A. A.M. 10 70-5 72-8 2-3 64 3 Cerura vinula (larva), A. A.M. 10 15 72-7 74-3 1-6 72 4 A.M. 10 30 66 5 A.M. 1 1 73-5 64 6 Cerura vinula (larva), A. A.M. 11 15 73-5 74-8 1-3 71 7 Cerura vinula (larva), A. 17 a.m. 5 30 69-5 70 •5 47 8th day. 8 Cerura vinula (larva), A. A.M. 7 71-4 72-3 •9 64 9 Cerura vinula (larva). A. a.m. 7 30 72 72-9 •9 57 10 Cerura vinula (larva), A. a.m. 7 45 72-3 72-9 •6 55 11 Cerura vinula (larva), A. a.m. 8 72-5 73-2 •7 56 12 Cerura vinula (larva), A. A.M. 9 72-2 73-2 1-0 68 13 Cerura vinula (larva), A. a.m. 9 15 72-2 73-3 1-1 59 14 Cerura vinula (larva), A. a.m. 9 30 73-1 74-2 11 70 15 Cerura vinula (larva), A. a.m. 9 45 73-2 74-4 1-2 68 16 Cerura vinula (larva), A. A.M. 10 15 73-2 74-3 11 67 17 Cerura vinula (larva), A. A.M. 11 74-4 75-7 1-3 72 18 Cerura vinula (larva), A. a.m. 12 45 78-5 80 1-5 77 19 Cerura vinula (larva), A. P.M. 1 15 78-5 80-2 1-7 78 20 Cerura vinula (larva), A. p.m. 4 45 80-5 81-9 1-4 88 21 Cerura vinula (larva), A. p.m. 5 30 80-4 81-2 •8 88 22 Cerura vinula (larva), A. 18 A.M. 7 75-2 761 •9 66 9th day. 23 Cerura vinula (larva), A. a.m. 8 30 75-4 76-3 •9 68 24 Cerura vinula (larva), A. A.M. 9 76-1 77 •9 72 25 Cerura vinula (larva), A. 19 A.M. 7 70-7 71-4 •7 60 10th day. 26 Cerura vinula (larva), A. a.m. 7 30 70-9 71-8 •9 60 27 Cerura vinula (larva), A. A.M. 8 70-7 71 0-3 54 28 Cerura vinula (larva), B. 16 a.m. 10 30 71-8 72-3 •5 49 29 Cerura vinula (larva), B. A.M. 10 45 71-8 72-5 *7 30 Cerura vinula (larva), B. 17 a.m. 5 30 68-5 68-7 •2 31 Cerura vinula (larva), B. F.M. 1 15 78-5 78-9 •4 50 32 Cerura vinula (larva), B. p.m. 4 45 78-9 79-2 •3 46 33 Cerura vinula (larva), B. 19 a.m. 7 30 70-9 71-3 •4 31 Remarks. / Just captured, and confined in my box in my \ pocket, perspiring copiously. Insect active, but more calm ; pulse full, sinking. Very active, in constant motion, pulse small. Has rested a few minutes, asleep. Has been sleeping half an hour. Aroused and excited. Has been sleeping during several hours. Moderately active. At rest. Sleeping. Still sleeping. Active, and feeding. Resting. Feeding. Still feeding. Active, but not feeding. Very active. Very active. Still very active. Moderately active. Less active. Sleeping, or quiet. Quiet. Aroused and feeding. Changing colour for transformation. More discoloured. Preparing to spin its cocoon. After feeding 36 hours, just fed, sleeping. A little active. Is spinning its cocoon for transformation. Still spinning its cocoon. Still spinning. Has been retarded from changing. But it is not only at the period of change into the pupa state that the pulsation is greatly reduced, the same thing takes place immediately before each change of skin in the larva, as shown on Table IX. Nos. 9, 23, 34, and 63. At those periods the temperature and respiration are also reduced, and the insect ceases to eat ; but soon after the change of skin has taken place the respiration and temperature are again increased ; but the average rate of pulsation is never so great as before the previous change of skin, and it continues to be diminished at each succeeding change. The following observations made on larvae of Sphinx ligustri of the same age, at different periods after entering their fifth or last skin, and when the pulse in each was regular and full, will further illustrate the general accordance which exists between the rate of pulsation and amount of temperature when the pulsation has not been accelerated by inordinate activity or other causes. 2 t 2 318 MR. NEWPORT ON THE TEMPERATURE OF INSECTS. Table XI. Period of observa- tion. No. Age of the Insects. Atmo- sphere. Insect. Differ- ence. Pulse. July 31,1834. 1 Three davs in last skin, feeding 0 71-2 0 72-3 fi 54 2 Three days in last skin, resting 71-2 72-2 1 49 3 Five days in last skin, feeding 71-2 72-2 1 49 4 Five days in last skin, feeding 71-6 72-6 1 50 5 Seven days in last skin; has been long sleeping ... 71-2 71-6 •4 29 6 Seven days in last skin ; aroused and active 71-6 72-4 •8 38 The same general accordance which exists in the larva between the quantity of respiration, amount of heat developed, and number of pulsations, exists also in the perfect insect. In order to observe the number of pulsations in the perfect insect it is necessary to denude the dorsal surface of the abdomen of its thick covering of scales, and when this has been done completely the pulsation of the vessel is readily observed. In a male specimen of Sphinx ligustri which had been exerting itself in active flight for several minutes around my sitting-room, I found the number of pul- sations was 127 per minute, while the insect then had a temperature of 9° Fahr. above that of the atmosphere, which was 70° Fahr. On the following day, after it had been exerting itself in a similar manner for a much longer space of time, the temperature of the atmosphere being 690,5, the number of its pulsations was then 139, and its number of respirations forty-two per minute, but its amount of heat was only 50,5 Fahr. When it had remained at rest about half an hour its temperature was only °-5, while the number of its respirations was eighteen, and of its pulsations forty-nine ; and at the expiration of three quarters of an hour, when it was perfectly quiet and apparently asleep, its temperature was only 0-2, its number of respirations fifteen, and its pulse forty-two. In these instances the accordance between the number of respirations and pulsations, and the temperature of the insect was nearly uniform, but in some of the other observations the same uniformity between the amount of heat developed and the number of pulsations is not so strictly observed. Thus in No. 12, Table V., the temperature of the insect after violent exertion was 9° Fahr., the number of pulsa- tions 127, while in No. 14 the temperature was only 40,6, but the pulsations amounted to 151 ; and in No. 15 the temperature was 40,3, but the pulsations only 110. It is thus evident that in the perfect insect, as in the larva, there are sometimes similar irregularities in the rate, or velocity of pulsation, and which irregularities when compared with each other do not appear to have relation to the quantity of heat developed, while the general, or what appears to be the average rate of pulsa- tion, is in almost uniform accordance with the amount of heat and number of respi- rations. But these apparent discrepancies may, perhaps, be explained by the circum- stance, that when the pulsations are excessive in number they are small, rapid, and intermittent, like the pulsation in certain excited states in the human body, and this is the case in every instance of excessive pulsation, both in the larva and perfect in- sect ; while in those instances in which there is a near accordance between the rate of pulsation, amount of heat developed, and number of respirations, the pulsatory motions are full, regular, and without intermissions, so that the relative quantity of MR. NEWPORT ON THE TEMPERATURE OF INSECTS. 319 blood which is steadily submitted to the influence of the air in the respiratory organs is perhaps greater in the latter than in the former instances. This circumstance may also account perhaps for the smaller amount of heat generated by the larva in its earlier than in its latter condition, although the number of its pulsations is more than double in the earlier than in the latter period. In the full grown larva the pulsations are steady and full, with much power, but in the earlier state of the larva they are small, rapid, and intermitting. From these circumstances we may fairly infer that the quantity of heat developed is more dependent upon the quantity of respiration than upon the velocity of the circulation. 3. Digestion. The influence which the process of digestion exercises over the production of heat is very considerable. We have before seen that in the larva the greatest amount of heat is produced after the insect has fed, or while it is feeding and becoming much excited. It is at these periods that it deteriorates the greatest quantity of air, which quantity is then necessarily required during its respiration in assimilating the new matter which has just been taken into its circulation through means of the digestive process. In the perfect insect the circumstances are exactly the same, its temperature is greatest after it has fed, and is then exerting itself, and at that time it respires the greatest quantity of air. On the other hand, when the insect is fasting, the quantity of heat evolved by it, even during great exertion, is much diminished, while the quantity of air consumed is smaller than the quantity consumed under similar excitement after it has taken food. 4. Gaseous , or Cutaneous Expenditure of the Body. The cutaneous expenditure of the body is closely connected, both with the digest- ive process and with the regulation of the temperature of the insect. It is seen in the observations on Melolontha solstitialis and other species, that the amount of gaseous expenditure is exceeding great, and that after the temperature of the insect has been raised to a certain amount, a profuse perspiration breaks out, which is the natural cooling process of the body. The pulse also is considerably affected by it, as shown in the larva of the Puss Moth, which had been subjected to high tempera- ture, and which soon became bathed in perspiration. Table X. No. 1 and 2. The exact correspondence which exists between the quantity of gaseous, or cutaneous ex- penditure, acceleration or subsidence of the pulse, increase or decrease of weight, and quantity of respiration in every period of the larva, pupa, and perfect state, is very remarkable. The quantity appears to be at its maximum in the very active perfect insect, and is greater than in the larva, or in the pupa, in which it is at its minimum when the pupa has the smallest amount of respiration; but in all cases it is least during the state of most complete inactivity. In the common Hive Bee in a state of activity the amount is prodigious, and very soon becomes evident, if the bee be con- fined in a very small glass phial, closely stoppered, and kept in a state of excitement. The perspiration from the insect is then condensed upon the interior of the phial, and if several bees be confined together, the bodies of the little insects themselves become 320 MR. NEWPORT ON THE TEMPERATURE OF INSECTS. bathed with perspiration. In the summer of 1832, I endeavoured to ascertain the quantity of gaseous expenditure in the larvae of Lepidoptera compared with the weight, quantity of food eaten, increase, and faecal expenditure of the insect, in a given time, and it was then found that the quantity of gaseous is equal to, or even greater than the quantity of faecal expenditure, even in these animals in which the latter is so enormous. The first subject of my observations was my old favourite, the larva of Sphinx ligustri. The specimen on which my observations were com- menced had been confined fasting about twelve hours, when it weighed 79’ 8 grains, having at the commencement of the twelve hours weighed 83*3 grains. During this period of fasting it had passed two masses of faeces, which weighed only 1’7 grain, consequently it had expended by the skin and respiratory organs 1’8 grain, an excess of one tenth of a grain in the gaseous expenditure. It was then supplied with fresh food, of which it ate 2’8 grains, and weighed 82’ l grains at the expiration of the first hour ; had passed no faeces, but had expended ’5 of a grain from the skin and respiratory organs. It was then made to fast for an hour, and afterwards weighed again to ascertain whether there was any difference in the quantity of gaseous ex- penditure during abstinence. It had discharged one mass of faeces weighing ’9 of a grain, and itself weighed 80’8 grains, so that during the hour of fasting only •4 had passed off in the gaseous form instead of "5 as in the previous hour of taking food. At this time, while the insect was lying at rest, the dorsal vessel pul- sated at the rate of thirty-six beats per minute. The insect was then allowed to feed for another hour and weighed again; at the expiration of that time it had passed no feces, had eaten 3’4 grains of food, and weighed 83’6 grains. Thus one whole grain had now been expended in the gaseous form. It then fasted for three hours, but during that time it passed only one mass of fseces, which weighed 1*2 grains, and itself weighed 81’6, so that it had now lost only ’8 in the gaseous form during three hours’ fasting. It was thus evident that the greatest amount of gaseous expenditure occurs during the period of taking food, and that the quantity of gaseous expenditure decreases in proportion to the length of time the insect is kept fasting, and also that less gaseous expenditure takes place when there is the greatest amount of fecal, When the insect had been fed for another hour, and had eaten 2*7 grains of food, it weighed 83’9, but had passed no feces, consequently it had now expended ’4 of a grain in the gaseous form. It was thus evident that the quantity which passes off in the gaseous form during a certain length of time when the animal is taking food varies considerably, and sometimes amounts to one whole grain per hour, while at other times it is only about ’4 of a grain. These observations were continued through two successive days, wilh similar results. Thus after the insect had been fasting for twelve hours, during which time its amount of gaseous expenditure had been very trifling, the very first time it was weighed after feeding for one hour it had expended ’5 of a grain ; but when it was kept fasting, the very next hour its expendi- ture was only 4 of a grain. Similar experiments were also made at the same time upon the larvae of the Puss Moth, Cerura vinula, Steph., and Sphinx Elpenor, Linn., with precisely the same results relative to the quantity of gaseous expenditure. In MR. NEWPORT ON THE TEMPERATURE OF INSECTS. 321 the observations on the Sphinx ligustri, it will be seen by the Table XII. that the heat developed during fasting is much less than during' the period of taking food. Table XII. — A Table* exhibiting the quantity of food eaten, with the rate of increase of weight, and the gaseous and faecal expenditure, and their effect on the Tempe- rature of a Larva of Sphinx ligustri. No. of Exp. Period of Observation. Feeding. Fasting. o c/5 d, | s-i <2 O c Difference. Weight of I larva in 9 grains. j Weight of food eaten in grains. Increase, j Gaseous ex- | penditure. 1 Faecal ex- penditure. Remarks. 1832. o o o grs. 1 Twelve hours 79-8 2 One hour 82T 2-8 2-3 •5 3 A.M. 12 One hour 80-8 •4 •9 4 One hour 83-6 3-4 2-8 •6 5 81-6 •8 1-2 6 One hour 83-9 2-7 2-3 •4 7 P.M. 6 One hour 85-1 4-5 1-2 2 1-3 8 P.M. 7 One hour 85-6 3-2 •5 2-7 9 P.M. 8 One hour 85 1-5 •6 1-5 10 P.M. 9 One hour 86-5 2-1 1-5 •6 11 Aug. 19 p.m. 9 to 20 a.m. 6 Nine hours ... 88 16-5 1-5 7 8 12 A.M. 7 One hour 87-6 •4 13 A.M. 8 *# ** 85-6 •4 1-6 14 A.M. 9 •5 85-55 •05 15 A.M. 10 One hour 65-9 •4 85-5 •05 16 A.M. 1 1 One hour 70 •6 85-4 •i 17 A.M. 12 One hour 67 67-7 •7 85-2 •2 Active. 18 P.M. 1 One hour 68 68-7 •7 85 •2 19 P.M. 2 One hour 69 69-4 •4 83-6 •05 1-35 20 P.M. 3 One hour 69 5 69-7 •2 83-55 •05 21 P.M. 4 One hour...... 70-4 •9 86-1 3-6 2-55 1-05 22 P.M. 5 One hour 70- 1 7M 1 3-6 2-75 •85 23 P.M. 6 One hour 69-5 70-4 •9 89-15 2-4 •3 1 1-1 24 P.M. 7 One hour 69 70-1 11 90 1-8 •85 •95 25 Aug. 20 p.m. 7 to 21 a.m. 7 Twelve hours 68-5 69-4 •9 92-6 25-5 2-6 11-6 11-3 Sleeping. 26 A.M. 8 One hour 68-7 69-9 1-2 93-9 1-95 1-3 •65 27 A.M. 9 One hour 69 70 1 94-65 4-4 •75 2-1 1-55 Active. Total increase in 47 hours... 14-85 79-95 35-3 29-8 A Table exhibiting the gradually decreasing amount of Wei ght and Gaseous Expen- diture in proportion to the length of time of fasting in a Larva of Sphinx Elpenor. 28 65-3 29 66-4 65-1 •2 30 67 64-9 •2 31 P. M. 1 68 64-8 •1 32 P. M. 2 69 64-7 •1 33 ’ P.M. 3 69-5 64-65 •05 34 69-5 64-5 •15 35 70-1 64-4 •1 36 69-5 64-2 •2 Very active. 37 P.M. 7 69 64 •2 38 A.M. 7 68-5 162-15 1 39 A.M. 8 68-7 62 •15 Very active. 40 A.M. 9 One hour 69 63-65 3-45 1-65 1-8 Total decrease in 23 hours.. 1-65 4-25 •85 * These Tables on the quantity of food eaten, loss and increase of weight, gaseous and fsecal expenditure, and temperature of the atmosphere at the time of making the observations, were made, as noticed below, in August 1832 ; but the two columns which indicate the temperature of the insect** were not made at that pe- riod, hut have been added subsequently, having been made in the summer of 1834 upon the larva of the Sphinx under circumstances similar to those of August 1832. Indeed from the precautions necessary to be attended to while taking the temperature of the insect, as noticed in the beginning of the present paper, it will be seen that it is impossible to make the whole of the observations here detailed upon the same individual at the same time, the excitement produced in the insect while handling it in order to ascertain its weight unavoidably inter- fering with the correctness of the observations on its temperature. Two specimens therefore of the same weight and age must always he employed. 322 MR. NEWPORT ON THE TEMPERATURE OF INSECTS. Table XII. (Continued.) A Table of the Weight and Rate of Increase and Decrease, with the Faecal and Ga- seous expenditure of a Larva of Cerura v inula. No. Period of Observation. 1832. Aug. 20a.m. A.M. A.M. A.M. P.M. P.M. P.M. P.M. P.M. P.M. P.M. A.M. A.M. A.M. 9* lot lit 12t H 2t 3t 4t 5t 6t n 7k 8t 9t Feeding. Fasting. Temp, of Atmos. Insect. Difference. | Weight of larva in grains. Weight of food eaten in grains. Increase. | Gaseous ex- | penditure. I o o grs. 65 76-5 65-5 78-1 3-65 1-6 1-55 b 66-4 77-2 2-4 1-45 67 77-6 2-55 •4 1-2 68 76-6 1-6 1-25 69-5 76-3 2-5 1-45 69*5 74-95 2-1 1-05 70 75-9 4-4 •95 21 70-2 74-4 1-75 ]-l 69-5 75-05 2-7 1-25 69 |75-7 2-1 •65 •95 68-5 ‘69-75 2-55 68-7 ‘69-65 •1 One hour 69 711 I 3-7 1-45 1-75 fa o. •5 1-55 •95 1 -35 1 "35 2 1 1-35 215 •8 •5 4-6 Remarks. This larva was fed throughout -the whole of the observations upon stale food. Decrease in Weight in 26 hours 5'4 Food eaten 29-45 17-75 11-70 From this Table we deduce the following facts : — First that the expenditure which takes place from the cutaneous surface of the insect and from its respiratory organs is greater than its whole amount of faecal expenditure, is more regular and con- tinued, and decreases in proportion to the length of time which the insect remains fasting, but never entirely ceases. It is greatest while the insect is in motion and least when it is lying entirely at rest. Thus in the observations on Sphinx Elpenor, Linn., which was fasting during nearly the whole of the period of observation, twenty- two hours, the insect lost only ’85 of a grain of faecal expenditure, but 2’45 of grains by the respiratory and cutaneous surfaces, and of this expenditure, when the insect was lying at rest, only ’05 of a grain per hour, but when in violent motion the loss amounted to *15 per hour. This difference of quantity is readily accounted for by the quicker circulation of the fluids in the active state of the insect, when its respira- tion is greater, and consequently a greater amount of heat is generated, and requires to be regulated by the transpiration from the surface of the body. This Table also indicates the fact that the whole process of digestion may be completed in the larva of the Sphinx in about two hours and a half, and that the average quantity of faecal expenditure in the latter period of a moderate sized larva is about one grain per hour. But the connection or correspondence between the quantity of respiration, tempe- rature and gaseous expenditure in a given time, is beautifully illustrated in what oc- curs in the pupa state. On the 3rd of April, 1836, 1 weighed several pupae of Sphinx ligustri, and found that one of them which on the 20th of the preceding August, im- mediately after it had changed to a pupa, weighed 71 '1 grains, had not expended, during the long interval of nearly eight months, or two hundred and twenty-eight days inclusive, more than 37 grains in weight, the whole of which must have passed oft from the respiratory and cutaneous surfaces. This was the identical specimen which I MR. NEWPORT ON THE TEMPERATURE OF INSECTS. 323 had watched from the egg, and whose rate of pulsation is noticed on Table IX. At the time of entering into the pupa state in August, it weighed, as above stated, 7 IT grains. At the present time it weighed 67‘ 4 grains. This diminution was during the period of hybernation, and is in beautiful accordance with the greatly diminished quantity of respiration during this state, respiration being reduced to its minimum in this condition of the insect, as shown in my previous observations. On the 24th of May, fifty-one days after the first weighing, the perfect insect was developed from this pupa, and then weighed only thirty-six grains, and when weighed again on the following day, only thirty-four grains, Table V. A, being an amazing diminution of nearly one half of the whole weight of the pupa in the short space of fifty-three days. Now it will be remembered that, as shown in the Tables on the Respiration* of the pupa of Sphinx ligustri in the month of April, that the quantity of respiration at that period is gradually increasing, and is in proportion to the degree of animation in the insect ; and the degree of animation is proportioned to the quantity of stimuli, external temperature, &c., so that, as shown by Reaumur in the pupae of the common Cabbage Butterfly, if the pupae be kept in a very low temperature, as in that of an ice-house, development into the perfect state is greatly retarded ; and as now shown, respiration, owing to the absence of a proper amount of external stimulus, being reduced to its minimum, the circulation of blood is almost suspended, the develop- ment of heat scarcely, if at all perceptible, and the expenditure of solid matter from the body of the insect in a gaseous form is so insignificant that the powers of life are in no way injured by retarded development, and the insect revives in its full vigour whenever the natural stimuli of life are sufficiently increased. At the moment of weighing the above pupa in April, I weighed several others which had entered the pupa state about the same time. One of them at the expiration of fifty-three days, on the 26th of May, had lost thirteen grains, another eight grains, a third nine grains, and a fourth ten grains, and the respiration of these had increased in the ratio of their loss of weight. There may, perhaps, be some difficulty in ascertaining with certainty the chemical constituents of this gaseous expenditure from the body of the insect in its different stages, since a large proportion appears to be aqueous vapour, but I am satisfied that sometimes there is also a quantity of carbonic acid. However, I could not discover the carbonic acid in a quantity of vapour expelled from the bee hive and condensed during the night, but I very readily detected it in the pupa, in my earlier observations on the respiration of insects, in April 1829. A pupa of Sphinx ligustri, after being carefully washed to prevent the adhesion of air to the surface of its body, was placed for a few hours in a glass stoppered phial, completely filled with perfectly clear lime- water, and at the expiration of two or three hours, I had the satisfaction of detecting carbonate of lime deposited both within the entrance of the spiracles and also in the minute punctures which are distributed over the whole body of the pupa ; a certain * Philosophical Transactions, 1836, Part II. p. 552, Table I. No. 3 to 10. mdcccxxxvii. 2 u 324 MR. NEWPORT ON THE TEMPERATURE OF INSECTS. proof this, both that the pupa was transpiring through the pupa case, and also that the transpired matter contained carbonic acid. Conclusion . The very great length unto which this paper has already been extended, neces- sarily prevents me from entering so fully into all the circumstances connected with the evolution of heat in insects as the great importance attached to this interesting subject demands ; I shall, therefore, review the contents of this paper, and other cir- cumstances connected with the production of animal heat, with as much conciseness as possible. On comparing the whole of the facts we have just examined, we cannot fail to ob- serve the very close relation which subsists between the amount of heat developed, and the quantity of respiration. We have seen in the larva, the pupa, and the perfect insect, -that when the respiration is accelerated the temperature is also in- creased, and that when respiration is diminished the temperature subsides. When the insect is sleeping, its respiration gradually becomes slower, and its temperature continues to lessen until the insect is aroused, when immediately after the first respi- rations it is again increased. When the insect falls into a state of hybernation, and its respiration is suspended, its evolution of heat becomes so likewise. When the insect is most active, and respiring most voluminously, its amount of temperature is at its maximum, and is very great, and corresponds with the quantity of respira- tion, and, as in the Bee, an immense quantity of heat passes off into the surrounding medium. When the insect wishes to impart heat to its young it can do so at plea- sure, and can voluntarily increase its own temperature. It does this by accelera- ting its respiration. At those times, as shown in the comparative observations, the insect evolves in one hour, in this state of activity and excitement, at least twenty times the amount of heat, and consumes nearly twenty times the quantity of air, which it consumes at the same temperature when in a state of repose. In insects which live in society the temperature of their dwellings is increased in proportion to the activity of the inmates, and consequent amount of their respiration. In the hive it is steadily increased until the time of swarming. In the winter when the bees are quiet, and their respiration is exceedingly low, and when not a bee is observed venti- lating at the entrance, the temperature of the hive may be raised in a few minutes, very many degrees, by disturbing the inmates, and thereby increasing their respira- tion, until such an amount of heat is evolved, and so much air is deteriorated, as to become oppressive and noxious to the bees, many of whom, although the open atmo- sphere be too cold for them to venture abroad, will come to the entrance of the hive and begin as laboriously to ventilate the interior, by vibrating their wings, as in the midst of summer. The quantity of free heat is always greatest in the hive when the bees are most active, and least when they are most quiet. With regard to the habits and anatomical structure of insects, the amount of heat is by far greatest in volant MR. NEWPORT ON THE TEMPERATURE OF INSECTS. 325 insects ; these always have the largest respiratory organs, and breathe the greatest quantity of air. In the terrestrial insects the amount of heat is greatest in those which have the largest respiratory organs, and breathe the greatest quantity of air, whatever be the condition of their nervous system. In the larva state the respiratory organs are smaller than in the perfect insect, compared with the size of the body, and the larva, we have seen, has the lowest temperature. But in these comparisons we must observe that the activity of respiration is equal in the individuals which are compared. Thus although the respiratory organs are larger in the pupa than in the larva, the phy- siological condition of the insect is lower, its respiration is inactive. These facts, it will be seen, are all in strict accordance with each other, and point to the chemical changes in the air during respiration as the immediate source of animal heat. But it may be matter of inquiry how it is that the heat evolved within the body of the insect, during respiration, becomes evident so rapidly. This, it may be urged, tends to show that it results from the influence of the nervous system. But when we remember that in insects the circulatory vessels are in close and most extensive communication with the respiratory organs over the whole body of the individual, and that, unlike the vessels in those vertebrated warm-blooded animals which have extensive respira- tion, they are neither strictly venous nor arterial, but probably intermediate between the two, may it not arise from only a very small amount of heat evolved at each re- spiration becoming latent, while nearly the whole becomes free, and is liberated as quickly as produced, and that this is the occasion of the temperature of the insect being so quickly raised during its respiration, and so rapidly diminished as the acts of respiration become less frequent? That, in other words, in insects the capacity of the blood for caloric is but very little increased during respiration? With these facts in consideration, and looking at the analogical condition of insects, and with Pro- fessor Grant* and Mr. OwEN'f'-, comparing the vast extent of their respiratory organs, distributed over the whole body, with a like extensive respiration in birds, and finding that, like birds, insects have also a greater activity of respiration, and a higher tem- perature of body than any other class in the division of animals unto which they re- spectively belong, we can hardly withhold our assent to the opinions which have long been advocated by many of our best physiologists, that animal heat is the direct result of the chemical changes which take place in the air respired. But it may be urged that activity of respiration is coincident with increased rapidity of circulation, and hence that the latter may, perhaps, precede the former, and be in reality the source of heat. Unto this it may be replied that the larva in its earlier state has a more rapid circulation, but develops less heat than in its latter. In many of the observa- tions on tbe Tables it is shown that the pulse may be rapid with a low amount of heat. It is shown in the larva, when arousing, that the pulse is not increased until * Lectures on Comparative Anatomy. — Lancet, 1833-34. f Cyclopaedia of Anatomy and Physiology, vol. i. p. 341. 2 u 2 326 MR. NEWPORT ON THE TEMPERATURE OF INSECTS. after the first respirations*, when the heat is becoming apparent. With regard to the digestive process, we have seen that when the animal is taking food it has the greatest amount of gaseous expenditure from its body, and that the greatest amount of heat, when in a state of quietude, is then generated. But a, greater quantity of air is then consumed, in assimilating the new matter which has been taken into the sy- stem, and the quantity of heat is still further increased if the animal becomes active, and this is regulated by the increased expenditure from the surface of the body. Lastly, we have seen that in the more perfect volant insects, the Bees, Sphinges, &c., there is the largest amount of heat produced, and the greatest quantity of air con- sumed, but the nervous system is also largely developed, and hence it may fairly be supposed to have much influence in the development of heat. But on the other hand we find many insects, as the Meloe and its congeners, which produce a large amount of heat, in which the nervous system is comparatively small, while these insects have large respiratory organs, and a large amount of respiration. In the Staphylimis the nervous system is exceedingly large, compared with the size of the body, but the re- spiratory organs are by no means small, while the amount of heat is very moderate. In the Carabus the nervous system is also large, as are likewise the organs of respi- ration, but the amount of heat and activity of respiration are low, and the same is the case in the Blaps, in which the nervous system is rather small. If the development of heat depends upon the nervous system, or the number of ganglia, the Leech, which has twenty-two ganglia, ought to generate more heat than the larvae of lepidopterous insects, which have but ten or twelve, and the larva ought to generate as much as the perfect insect. In the larvae of the Bee, the Hornet, Ichneumon, and Tenthredo, which generate so large an amount of heat, the nervous system is exceedingly small ; and if, as some suppose, heat is the result of muscular contraction, surely it ought to be most developed where there is the greatest amount of muscular contractility; it ought to be generated more in the Leech than in other articulated animals, and in those Vertebrata which are peculiarly noted as cold-blooded. These facts con- * This is in perfect accordance with the condition of the circulation in the human body during sleep, and at the moment of waking, as noticed by Blumenbach, and as I myself once had an opportunity of observing in a female patient who was suffering from severe fracture of the skull, for which she had been trephined ; subse- quently to which, a large portion of the bone (the right parietal) became affected with necrosis and was removed by operation, and the patient afterwards gradually recovered. At least one-third of the whole parietal bone had been removed, and a large surface of the dura mater being thus exposed, the activity of the circulation in the brain was readily observed. I thought this a fair opportunity, as the patient was recovering, for observing the state of the circulation during sleep, and at the moment of waking. The patient was sleeping soundly at the time of the observation, and while she remained entirely undisturbed, the pulsations in the arteries of the dura mater were at the rate of ninety-four beats per minute, and were perfectly synchronous with the pulsations at the wrists ; but immediately she began to inspire deeply at the moment of waking, the pulsations became much accelerated. At the instant of waking, the patient fetched a full and deep inspiration, and in less than a minute and a half after this, the patient being perfectly awake, the pulsations amounted to 104 beats per minute, thus making a difference of about 600 beats per hour in the rate of pulsation when sleeping and immediately after waking. MR. NEWPORT ON THE TEMPERATURE OF INSECTS. 327 sidered, and connected with that very remarkable one, the voluntary power of pro- ducing heat possessed by the Bee, must lead us to conclude, that although, doubt- less, the whole of the functions of the body are more or less remotely concerned in the production of heat, yet that the immediate source of its evolution seems to be chemical changes effected during respiration, and that the nervous system is only secondarily concerned. Appendix, Since the preceding paper on the Temperature of Insects was submitted to the Royal Society, circumstances have enabled me to ascertain a few additional facts respecting the temperature of some other species which I had not heretofore any opportunity of examining, and these the Council have kindly permitted me to subjoin to my paper. I am not aware that the temperature of the nest of the common wasp has ever before been examined, and it is therefore pleasing to find that all the circumstances connected with the evolution of heat in the nest of this species are in perfect accordance with the observations made on the neighbouring families of hive and hum- ble bees. On the 11th of August, during the past summer (1837), I dug away the soil from the top of a nest of Vespa vulgaris which was situated in a bank of earth at the depth of about seven inches from the surface. The nest was nine inches in diameter, so that the colony was by no means a small one. The temperature of the atmo- sphere, when the covering of the nest was removed, at 4| p.m. was 70° Fahr. When the thermometer was passed through the top of the nest the mercury rose immediately to 80°. In about ten or fifteen minutes afterwards, when the colony had become disturbed, and the thermometer was passed a little deeper into the nest, the mercury rose to 95°. This distinctly proves that the evolution of heat in the wasps’ nest is greatly increased, as in the beehive, when the insects have become excited. At p.m. the temperature of the atmo- sphere was 65° Fahr., and the wasps having now become more quiet, the temperature of the nest, which had remained with its upper surface exposed since the last observation, was only 90° Fahr. ; but an hour afterwards, when the temperature of the atmosphere had sunk to 63°, that of the nest had risen to 91°, the thermometer having remained undisturbed in the nest since the last observation. This increase of temperature was readily explained by a great number of the excited insects, which had been flying around the spot, having now returned to the nest. Thus the circumstances connected with the evolution of heat in the nests of the predaceous and in the melliferous Hymenoptera are precisely similar ; and they are similar also in another interesting family of this order — the ants. It is elsewhere noticed* that Juch found the temperature of an ant-hill about 15° Fahr. above that of the atmosphere. My own observations are in accordance with this statement. On the 27th of July 1837 I examined the temperature of the nest of Formica herculanea, Linn. The temperature of the atmo- sphere in the shade, at 1 1 a.m., was 7 6° Fahr., but when the thermoipeter was exposed on the ground to the full rays of the sun the mercury rose to 95° Fahr. The nest was rather a small one, and at the time of commencing the observations was completely undisturbed. When the thermometer was first passed into it, to the depth of five inches, the temperature was maintained steadily at 84° Fahr. ; but within six or eight minutes afterwards, when the insects had become excited by the presence of the thermometer, and were running about in every direction in a state of the greatest agitation, the temperature of the nest rose to 93° Fahr., and in a few minutes after this, when the insects were still more excited, to 95°’5, and a little nearer the surface, where the commo- tion was greatest, to 98°'6Fahr. During these observations the ant-hill was carefully shaded from the rays of the sun, in order to avoid all source of error. When the ant-hill was again exposed to the sun, and the thermometer placed upon its surface, the mercury rose to 108° Fahr. This was a temperature much too great * Page 283. 328 MR. NEWPORT ON THE TEMPERATURE OF INSECTS. for the insects to bear, since nearly the whole of them immediately retired beneath the covering of the nest, and there was scarcely a single ant to be seen. On the 2nd of September I repeated my observations on the same ant-hill. On this occasion the day was very gloomy, with steady light rain, and the temperature of the atmo- sphere at 11 o’clock a.m. was only 54°. The temperature of the ant-hill varied but little in its different parts but it was now greatest near the surface. At a depth of one inch it was 6 5°, at two inches 66°, below which it gradually diminished. At this time I also examined another nest of the same species, but which was about twice the size of the first. The atmosphere being, as before stated, 54°, the mean temperature of this nest, when the insects were a little excited, was 74°. During the summer and autumn of the present year I have repeated my observations on the temperature of the bee-hive, and have found but little variation in its average amount at similar periods in the two years. I have also examined the nests of Bombus lapidarius, and Bombus sylvarum, and in both have found that the ordinary temperature, which is about 10° or 15° above that of the atmosphere, is considerably increased during the period of incubation, exactly the same as in the nest of Bombus terrestris. On the following day after examining the nest of the wasp, I examined the temperature and pulsation of the larva of the same species. The specimens examined had been removed from the nest on the previous evening, but had not been removed from their cells. The results are given on the accompanying table. I examined also the larva of the hornet, Vespa Crabro, Linn., which was still contained in its cell, but had been some days removed from the nest. In this instance the temperature of the larva was found to be about 20-5 Fahr. above that of the atmosphere, but its rate of pulsation was only thirty-two beats per minute. I should have attributed this low rate of pulsation to the specimen having been so long removed from the nest, had not the rate of pulsation in this larva been examined by my friend Mr. Orsborn a few days before, and almost immediately after the specimen was obtained from its nest, and found at that time not to exceed thirty-three or thirty-four beats per minute. These facts therefore are in accordance with the observations on the larva of Anthophora retusa and Bombus terrestris, and also accord with other observations on the larvae of that very destructive tenthredo or saw fly Athalia centi/olia, Klug ; which has been so obnoxious to the agriculturist by destroying his crops of turnips during the last three summers. London, November 1th, 1837. TABLE.— TEMPERATURE OF LARVAL No. of Exp. Name of Species. Period of observation. No. of Specimens. Atmo- sphere. Soil. Insect. Difference. Pulsation. Remarks. 1 July i o 70* o 725 o 2-5 32 Full grown; has fasted three or four days. 2 Vespa vulgaris (larva) Aug. 12 i 72-7 75-8 31 56 Nearly full grown; very active. 3 12 i 72-7 74- 1-3 52 Full grown. 4 12 i 72-7 75-2 2-5 52 Full grown. 5 50 64-5 66-5 2-0 Larva nearlv full mown : verv active. 3 6 64-7 66- 1-3 *' ° f * 7 6 66-3 66-8 0-5 Larva inactive. 8 9 Athalia (larvre) 6 6 200 50 05-3 65-3 67-3 67-3 2- 2- 1- Full grown ; active. 10 Melolontha vulgaris (larva) Oct. 7 1 61-5 59-7 60-2 0-5 No. 1. * 11 Melolontha vulgaris (larva) 7 1 61-5 59-7 60-3 0-6 No. 2. Full grown larva;; the temperature 12 Melolontha vulgaris (larva) 8 1 64-7 64-6 64-7 01 No. 1. taken while lying in their cells 13 Melolontha vulgaris (larva) 8 1 64-7 64-6 64-8 0-2 No. 2.1 and compared with the tempera- 14 Melolontha vulgaris (larva) 12 1 63-5 63-5 63-7 0-2 No. 1. ture of the soil. 15 Melolontha vulgaris (larva) 12 1 63-5 63-5 63-7 0-2 No. 2. MR. NEWPORT ON THE TEMPERATURE OF INSECTS 329 Table XIII. Showing the difference between the Temperature of the Atmosphere and that of the Bee-hive No. I, through many succeeding days, both when undisturbed and when excited. Period of observa. tion. Weather. Wind. Atmo- i sphere. Hive No. 1. Difference. o 36 49-5 50 o 14 Sunshine 55 5-5 Sunshine 53 62-5 9-5 i Twilight 66 15 Fine, brisk wind W. 53-4 58-3 4-9 Wind and rain W.S. 52 61-8 9-8 Windy, cloudy S.W.S. 53 60 7 Frost, calm, fine E. 405 52 11-5 . Dull, foggy, calm ... W.S. 53 55-3 2-3 High wind and rain s. 56 58 2 High wind, fine w. 48 53-8 5-8 High wind, fine w. 50 54 4 High wind, sunny ... w. 52-5 59 6-5 Strong wind, showery w.s.w. 52-9 57 4-1 Calm, cloudy W.S. 44 54 10 Fair, light clouds ... W.N. 40 49-5 9-5 Fair, light wind W.N. 41 49-4 8-4 Light wind, sunny... W. 50-5 51-9 1-4 Light wind, fine W.N. 50-8 58-7 7-9 Heavy clouds W.N. 44 52 8 Sharp hoar frost W.N. 28-5 45 16-5 Fair W.N. 30 52-5 22-5 Calm, fine W. 49-3 63-7 14-4 Calm, dull W. 48-3 57 8-7 Calm, foggy W. 44 56 12 Hard rain, wind s.w. 51 52-5 1-5 Dull, damp s.w. 57 67 10 Calm evening w. 51 61-5 10-5 Fair, misty E.N. 38 49-5 11-5 Fair, cold wind E. 51-5 54 2-5 Fair, signs of rain ... E.S. 51 65 14 Hard rain E.S. 50-5 60 9-5 Steady rain E.S. 49-5 58 8-5 Misty S. 52 56 4 Sunshine S. 53 59 6 Sunny, light clouds... W.S. 57-6 67-5 9-9 Fair W.S. 58 67 9 Calm, light clouds ... W.N. 50-6 76-5 25-9 Fine N.E. 39 56 17 Fine morning N.E. 42 57-5 15-5 Very fine N.E. 50-5 58-4 7-9 Very fine N.E. 51 65-4 14-4 Fair, calm W. 43-5 68 24-5 Fair, light clouds ... E. 39-5 51 11-5 Fair S.W. 55-5 58-3 2-8 Cloudy, rain s.w.w. 49-5 55-2 5-7 Misty rain S.E. 45 52-4 7-4 Light misty rain S.E. 47-5 52-4 4-9 Brisk wind S.E. 47 57-7 10-7 Wind S.E. 46 53 7 Fair, with clouds...... S.E. 43 49-7 6-7 Fair E. 43-5 49-6 6-1 Cloudy, wind E. 43-2 51-5 8-3 Rain with hail E. 42 50-5 8-5 Heavy clouds E. 43 49 6 Steady rain E. 45-7 49-7 4 Misty rain E. 44-6 49-8 5-2 Light rain E.N. 43 49-8 6-8 Hoar frost N.E. 32-7 441 11-4 Very calm N.E. 37-5 44-6 7-1 Calm, sunshine N.E. 41 45-3 4-3 Calm, sunshine N.E. 45 47 2 Excited. o « a Qi U £ 6 o o 67-5 80 18 27 59 5-6 71 18 50-5 10-5 73 22-2 76 24-5 83-5 255 78 80 27-5 29 70 26-5 Remarks. 1835. Oct. 23 A.M. A.M. P.M. P.M. 24 A.M. P.M. P.M. 25 A.M. 10 P.M. 2 11 26 a.m. 8 12 A.M. 8-1 13 A.M. 11 14 P.M. 2 15 P.M. 5|- 16 27 a.m. 6i 17 A.M. 8 18 a.m. 10 19 P.M. 2 20 P.M. 5i 21 28 a.m. 6J 22 A.M. 7\ 23 A.M. 10i 24 P.M. 2 25 P.M. 5 26 29 a.m. 7 27 P.M. 2i 28 P.M. 5 29 30 a.m. 6^ 30 A.M. 10i 31 a.m. 12 32 P.M. 2| 33 P.M. 5 34 31 A.M. 7 35 A.M. 10i 36 A.M. 12 37 P.M. 2 38 P.M. 5 39 Nov. 1 A.M. 6f 40 A.M. 8 41 A.M. 11 42 P.M. 2 43 P.M. 5 44 2 A.M. 7 45 P.M. 1 46 P.M. 6 47 3 A.M. 7\ 48 A.M. 10| 49 P.M. 3 50 P.M. 5 51 4 A.M. 7 52 A.M. 10 53 P.M. 2 54 P.M. 5 55 5 A.M. 7\ 56 A.M. 10 57 P.M. 2\ 58 P.M. 5 59 6 A.M. 7| 60 A.M. 9 61 A.M. 10 62 A.M. 11 Hive had remained undisturbed through the night. Bees readily excited. Bees active, loud humming in the hive. Hive slightly disturbed; cool evening. A few bees abroad, some return with yellow pollen. Not a single bee abroad; faint humming in the hive. Hive perfectly quiet. Bees beginning to hum, and becoming active. Hive quiet; a few bees abroad returning with pollen. Hive quiet ; tempestuous rain. Quiet; wind and rain tempestuous during the night. Quiet. Hive quiet, but few bees abroad. Faint humming in the hive ; few bees abroad. Twilight, hive quiet. Much rain in the night; bees irritable. Perfectly quiet. Many bees at the entrance of the hive; irritable. Few bees abroad ; soon excited. Twilight, slight humming in the hive. Slightly disturbed ; humming; morning calm. Quiet. Few bees abroad ; slight humming. Slight humming. Quiet ; calm damp foggy evening. Hive quiet; hard rain and wind during the night. Many bees abroad with orange yellow pollen ; irritable. Perfectly quiet. A few sounds heard in the hive. Many bees enter with pollen ; irritable. Bees abroad in numbers flocking home with pollen. Bees quiet; began to rain about 1 p.m. Quiet ; light wind. Quiet ; heavy continued rain during the night. Fine morning ; many bees abroad. Many bees abroad ; a few with pollen. Many bees abroad. Twilight, dull evening; slight humming. Light clouds ; sun just risen ; hive quiet. Quiet. Bees at entrance of the hive; very little pollen collected. Loaded bees numerous; quantity of pollen scanty. Quiet. Perfectly quiet. Hive quiet ; many bees abroad. Dark evening; hive quiet; beginning to rain. Quiet; light steady rain through the night. Quiet ; no bees abroad. Quiet; heavy clouds; signs of rain. Hive quiet; no bees abroad to day. Quiet; heavy clouds; cold wind. Quiet, but soon excited ; brisk sharp wind. Brisk wind; quiet. Quiet; brisk wind. Quiet; but little rain during the night. Quiet; heavy clouds. Slight noise in the hive ; light wind. Quiet. Rather misty; slight sound in the hive. Hive quiet. Hazy sunshine. Hive quiet. 330 MR. NEWPORT ON THE TEMPERATURE OF INSECTS Table XIII. (Continued.) Excited. Difference. o o 73-5 24-5 78-3 25-7 No. of Exp. Period of observa- tion. Weather. Wind. Atmo- sphere. O fe O > s Difference. 1835. 0 63 Nov. 6 p.m. H Calm, sunshine E. 47-7 53-7 6 64 PM. Calm, sunshine N.E. 45-5 51-7 6-2 65 P.M. 3 Calm, fair N.E. 44-9 50-6 5-7 66 P.M. 3* Calm, sunshine N.E. 45-3 49-5 4-2 67 P.M. 34 Calm, fair N.E. 44-7 49-1 4.4 68 P.M. 3| Calm, fair N.E. 44-5 48-9 4.4 69 F.M. 4 Calm, fair N.E. 43-4 49 5-6 70 P.M. 4* Calm, fair N. E. 41-5 48-1 6-6 71 P.M. 41 Calm, light clouds ... E. 41-5 53-9 12-4 72 P.M. 4f Light wind E.S.E. 40-5 50-4 9-9 73 P.M. 5 Cloudy S.E. 41-2 49 7-8 74 P.M. 54 More cloudy S.E. 41-7 50 8-3 75 7 A.M. 7 Very cloudy N.N.W. 41-5 46 4-5 76 A.M. n Light clouds N.N.W. 41-4 46-6 5-2 77 A.M. 74 Light clouds N.N.W. 41-7 46-6 4-9 78 A.M. 74 Sun peeping N. 42-2 46-5 4-3 79 A.M. 8 More cloudy N. 43-1 48 4-9 80 A.M. 84 Signs of rain N. 43-5 47 3-5 81 A.M. s§ Clouds breaking N.E. 44.7 47-4 2-7 82 A.M. 8f Fairer N.E. 45-6 47-5 1-9 83 A.M. 9 Fair N.E. 46-9 47-6 •7 84 A.M. 94 Light wind and clouds E.N.E. 47-7 48 •3 85 94 E.N.E. 48-7 48-3 86 94 E.N.E. 48-7 48-7 87 10 E.N. 49 88 A.M. lii Calm, dull E.N. 50-6 64-9 14-3 89 P.M. 1 Calm, dull E. 52-6 70 17-4 90 P.M. 3 Calm, fine E.S. 51-4 75 23-6 91 P.M. 5 Steady rain E.S. 49 70 21 92 8 A.M. 7 Light frost, calm W. 35 53 18 93 A.M. 9 Fine, calm w. 40-6 52-3 11-7 94 A.M. m Brisk wind N.W. 48 60-3 12-3 95 P.M. 2 Wind, sunshine N.W. 50 59-3 9-3 96 P.M. 5 Calm, clear N.W.N. 42-2 57 14-8 97 9 A.M. 74 Dull, light wind N.E. 40-6 49 8-4 98 A.M. 9 Cold wind N.E. 41-7 49 7-3 99 A.M. 10 Cold wind N.E. 42 49-4 7-4 100 A.M. 11 Cold, sunny N. 42-4 50-2 7-8 101 A.M. 12 Cold, sunny N. 43-6 49-7 61 102 P.M. 1 Cold wind N. E.N. 42-4 49-9 7-5 103 P.M. 24 Cold wind N.E. 41-9 50 8-1 104 P.M. 3 Wind and rain N.E. 39-3 49-5 10-2 105 P.M. 5 No rain N.E. 38 48 10 106 10 A.M. Cold brisk wind N.E. 107 11 A.M. 74 Hazy, cold N.E. N. 33 43-6 10-6 108 A.M. 9 Hazy, cold N.E. N. 35 43- 8 109 A.M. 10 Sun peeping N.E. N. 38-5 43-9 5-4 110 A.M. 11 Fine rain N.E. N. 40-4 44-4 4 111 A.M. 12 Light rain N. 41 45 4 112 P.M. 1 Dull, hazy N. 41-8 45-2 3-4 113 P.M. 2 Hazy N.N.W. 41-6 45-2 3-6 114 P.M. 4 Hazy N.N.W. 40 44-7 4-7 115 P.M. 44 Hazy N.N.W. 39-6 44-5 4-9 116 1 2 A.M. 74 Fine, light wind N. 35 43-4 8-4 117 A.M. 9 Fine, calm N. 40 43-3 3-3 118 A.M. 10 Fine, calm N. 43 44-2 1-2 119 A.M. 11 Fine, calm N.E.N. 45-6 45-4 120 A.M. 12 N.E.N. 46-6 46-3 121 r.M. 1 Sunny, clouds N.E.N. 48 48-1 •1 122 P.M„ 2 Heavy clouds N. E. 45-3 47-9 2-6 123 P.M. 3 Heavy clouds N.E. 42-6 47 44 121 r.M. 4 ! Ieavy clouds N.E. 41-2 41-2 125 13 A.M. 74 Light rain N.E. 36 43-7 7-7 Remarks. Loud humming in the hive ; a few bees abroad. A few bees return with a little pollen. A few bees still abroad, f A few bees abroad ; dew begins to condense on the t grass in the shade. Slight humming. Slight humming. Sky cloudless, but slightly hazy. Quiet. Light hazy clouds. Wind shifting. Thermometer varying. Signs of rain in the horizon. Hive quiet ; a little rain last night. Hive a little excited without evident cause. Hive quiet ; atmosphere clearer. Quiet. Slight humming ; clouds thickening from the east. Slight humming. Slight humming ; a few drops of rain have fallen. Slight humming. Hive quiet ; clouds dispersing. Slight humming. f Clouds dispersing; hive -4 of degree lower than the \ temperature of atmosphere. A few bees have been abroad, f When excited temperature of hive rose in 10 mi- \ nutes to 73/-5. Many bees abroad ; two have returned with pollen. Bees irritable ; many abroad ; a few with pollen. Many bees still abroad. Hive quiet. Quiet ; much rain fell last night. J Quiet ; cold, fine ; a few bees dead on the alighting \ board. Sunshine; many bees abroad. Bees abroad ; no pollen collected. Hive quiet; calm evening. Quiet; cold dull morning; no dew on the grass. Quiet ; cloudy. Quiet; cold brisk wind. No bees abroad. Quiet. Quiet. Quiet ; cold misty rain. Quiet; light driving rain. Quiet; cold wind with driving clouds. A severely cold day ; wind bitingly keen. Quiet; cold windy morning. Quiet; a little snow has just fallen. Slight humming ; a little snow falling. Quiet ; light rain. Quiet; sunny with rain. Calm ; dull. f A shrill humming at intervals of a single bee is [_ heard in the hive. Hive quiet. Quiet ; heavy clouds. Cold dry wind; hive quiet. Quiet; but excited by the slightest noise. Quiet; bright sunshine. f Quiet ; hive -2 of degree lower than temperature ol \ the atmosphere. J Hive quiet; ’3 of a degree the temperature of at- 1 mosphere. Slight humming ; a few bees abroad. Hive quiet. Quiet ; very heavy clouds passing. Quiet; signs of rain ; rainbow. Quiet; hard rain this morning. MR. NEWPORT ON THE TEMPERATURE OF INSECTS. ,331 Table XIII. (Continued.) No. of Exp. I Period of observa- tion. Weather. Wind. Atmo- sphere. Hive No. 1. 126 1835. Nov. 13 A.M. 9 Light rain N.E. o 37-3 o 43-7 127 A.M. 10 Light continued rain N.E. 37-6 43-9 128 A.M. 11 Light rain N.E. 39-6 44- 1 129 A.M. m Sunny N.E. 39-8 44-9 130 P.M. 2 Calm N.E. 41-6 45-8 131 F.M. 3 Rain E. 39-6 45-8 132 P.M. 4 Rain E. 38 45-2 133 14 A.M. 7 1 Calm, cloudy N.W.N. 35 43-2 134 A.M. 8 Calm, fair N.W.N. 35-4 43-2 135 A.M. 9 Calm, fair N.W.N. 35-4 47 136 A.M. 10 Calm, fair N.W.N. 39-4 46-3 137 A.M. 11 Calm, fair, cold N.E.N. 40-4 46-9 138 A.M. 12 Calm, fine E.N. 42-5 48-5 139 P.M. n Calm, fine E.N. 42-2 57 140 r.M. 4 Calm, fine E.N. 38 66 141 P.M. 4* Calm, fine evening N.W. 36 56 142 15 A.M. 8 Calm, fair N.E. 41 49 143 _ A.M. 9 Heavy clouds N.E. 42-6 50 144 A.M. 10 Sunny N.E. 45 50'2 145 P.M. 1 Bleak wind N.E. 47 54 146 P.M. 2 Cloudy, cold N.E. 45 ’4 53-6 147 P.M. Ai * 2 Heavy clouds N. 43-5 51 148 16 A.M. 7i Dull, cloudy W. 36-8 46 149 A.M. 84 Fair, light wind W. 37-6 46-2 150 A.M. 94 Fairer w. 40-3 46-4 151 A.M. 104 Dull sky w. 40-9 46-7 152 A.M. 1H Fair W.N. 44 47-1 153 A.M. 124 Fair W.N. 45-1 48 154 P.M. H Fair W.N. 44-7 48-1 155 P.M. 24 Fair W.N. 44 47-8 156 P.M. 34 Fair N. 40-8 47-2 157 P.M. Ai Calm, clear N. 37-6 46-7 158 17 A.M. 7 Misty, calm W. 39 45 159 A.M. 74 Misty, calm w. 39-5 45 160 A.M. 8 Misty, calm w. 40 453 161 A.M. 84 Misty, calm W.N. 40-6 45-4 162 A.M. 9 Misty, calm N.W. 41-4 45-3 163 A.M. 94 Misty, light wind N.W. 43-6 45-5 164 A.M. 10 Light misty rain N.W.W. 44-6 46-1 165 A.M. 104 Light misty rain W.N. 45-2 46-8 166 A.M. 114 Light misty rain Light misty rain W. 47-4 47‘4 167 A.M. 12 w. 48-2 48-1 168 A.M. 124 Light rain w. 48-4 48-1 169 P.M. 14 Clouds breaking w. 48-6 48-3 170 P.M. 4 No rain w. 47-6 48-5 171 18 A.M. 8 Very dull w. 47-8 48-2 172 A.M. 9 Brisk wind w. 49-2 48-9 173 A.M. 10 Brisk wind w. 51-4 49-7 174 A.M. 11 Brisk wind w. 52 50-9 175 A.M. 12 Brisk wind w.s. 52-6 51 176 P.M. 24 Brisk wind w.s. 51-9 51 -6 177 30 p.m. 3 Light rain s. 54-3 60 178 Dec. 2 p.m. 1 Fine, calm w.s. 51 75 179 P.M. 24 Fair, sunny w.s. 49 72-5 180 P.M. 3 Fair, sunny s.w. 48 73-5 181 P.M. 3 f Fair, calm s.w. 46-5 73 182 4 Fair, calm s.w. 46 183 3 A.M. 8 Windy, cold s. 49-2 71-5 184 A.M. 9 Brisk wind, cloudy s. 50 61-5 185 A.M. 124 Brisk wind, cloudy s. 51 60-7 186 P.M. 44 Brisk wind, cloudy S.S.E. 49-2 60-2 187 4 A.M. 10 Fair, calm w. 44-2 50-8 188 5 A.M. 8 Fine, clear w. 34 43-2 189 P.M. 4 Fine, calm S.W. 44 47 190 12 A.M. 8 Fine morning, light wind N. 23 39 0-4 6- 3 4-5 51 4-2 6-2 7- 2 8- 2 7-8 11-6 6-9 6-5 Excited. Difference. o o 67-3 31-9 69-5 29-1 6 57 14-8 65 28 .... 20 .... 8 ..„ 7- 4 .... 5- 2 .... 7 .... 8- 2 .... 7- 5 .... 9-2 .... 8- 6 .... 6- 1 .... 5- 8 31 2- 9 3- 4 3- 8 6- 4 9-1 6 5 -5 5-3 4- 8 3-9 1-9 1-5 1-6 14-5 22-8 5-7 24 23-5 25- 5 26- 5 22-3 11-5 9-7 11 6-6 9-2 3 16 2 x 80 79-8 78 72 25-7 31-8 32 49 ltemarks. Quiet; cold brisk wind. Quiet; less wind; gloomy morning. Quiet; very light wind; sky clearing. Clouds passing. Sunshine; bees attacked by the sparrows. Quiet; heavy clouds, with rain ; sky very gloomy. Quiet; heavy clouds. Hive a little disturbed. When the hive was excited temp, rose in 14m to G7,-3. Hive nearly quiet. Slight humming. f liaised in llm to 69' '5; bees appear, but return di- 1 rectly to the hive; air too cold. J Great excitement; temperature maintained at 57'; 1 bees ventilating, and going abroad. A few bees still abroad ; hive still excited. Slight humming; very fine evening. Slight humming. Hive quiet; atmosphere rather hazy. Humming; clouds passing. Clouds passing. Quiet; sky dark, cloudy. Faint humming ; wind bleak. Faint humming ; signs of rain. Faint humming. Hive quiet. Faint humming. Hive quiet. Humming. Humming. [ Quiet, excepting that the humming of a single bee [ is sometimes heard. Quiet. Quiet. Hive quiet; calm clear evening. Quiet ; dull misty morning. Brisk humming without evident cause. Hive more quiet. Quiet. Humming of a single bee. Quiet. Quiet. Quiet; no bees abroad. Quiet ; heavy clouds. Quiet; hive °-l of degree below the atmosphere. Quiet; °-3 of degree below. Quiet; 0-3 below; wind increasing ; no rain. Quiet ; cloudy. H:ve quiet; signs of rain. Hive quiet; °-3 below atmosphere ; cloudy. Quiet; 10,7 below the atmosphere ; sunshine. Quiet; 10,1 below; dull, cloudy. Quiet; l°-4 below; sunny, with clouds. Very quiet; °-3 below; a few bees abroad. Humming; bees undisturbed for the last 12 days. Many bees abroad ; excited without evident cause. Bees ventilating; still excited. Very irritable. Very irritable. Clear; mounlight. Air damp and cold ; bees abroad and very busy. Hive quiet ; heavy clouds. Hive quiet. Hive quiet. Light clouds and rain ; hive quiet. Hive quiet. Hive quiet. {Hoarfrost; has frozen hard during the last 36 hours; bees active, although entirely undisturbed durin the last six days; raised the therm, in llm to 49 above the temperature of the atmosphere. MDCCCXXXVII bco 332 MR. NEWPORT ON THE TEMPERATURE OF INSECTS Table XIII. (Continued.) No. of Exp. j Period of Observation. Weather. Wind. Atmo. j sphere. 1 Hive No. 1. 191 1835. Dec. 12 p.m. 1 Dull, cloudy W. o 38 o 47*8 192 P.M. 4 Dull, cloudy w. 36 56 193 13 p.m. 2 Fine, calm N.W. 41-2 45-2 194 14 A.M. 11^ Cloudy s.w. 42-6 45-6 195 23 p.m. 4 Clear frost N.E. 27 38 196 24 a.m. 12 Calm, misty N.E. 31 42-7 197 P.M. 4 Calm, hazy N.E. 29-5 42 198 25 a.m. 104 Calm, fine Cloudv, calm N.E. 23 38-4 199 27 a.m. 8 W. 29 39-5 200 P.M. 4 Cloudy, thawing W. 37 45-4 201 28 a.m. 8 Cloudy w.s. 42-7 45 202 29 p.m. 1 Fine w. 42-8 46-2 203 30 a.m. 8 Light cold rain N.W. 40 44-9 204 1836. Jan. 1 p.m. 2 High wind, sleet ... N.E. 3L5 44-1 205 2 A.M. 7j- Clear, intense frost... E. 17-5 30 206 A.M. 7| Sun just risen E. 16-5 63 207 A.M. 8^ Light wind E. 16-5 59 208 A.M. 84 Light wind E. 17-5 59 209 A.M. 9| Light wind E. 18-5 49 210 A.M. 12J Light clouds E.S. 30-7 46 211 P.M. 1^ Rather cloudy S.E. 32-3 49 212 P.M. 2^ Cloudy S.E. 31-2 45 213 3 A.M. 10 Light clouds W. 37 43-5 214 5 P.M. 1 Sunny, fair SAV. 50 55 215 13 A.M. 8 Hoar frost W. 28-5 45 1216 28 a.m. 8 Fair w. 43-5 59-5 217 February 19 a.m. 9 Fine day N.W. 35 47-5 218 A.M. 11 Fine day N.W. 39-2 48-2 219 P.M. 2 Fine day N. 48-5 50-2 220 20 a.m. 8 Fine, calm N.E. 24 44 221 A.M. 10 Fine N.E. 34-5 48-5 222 A.M. 11 Light clouds E. 39-5 48-1 223 L__ P.M. 2? Very' fine E. 41-8 58-5 9-8 to 4 3 11 11- 7 12- 5 15-4 10-5 8-4 2- 3 3- 4 4- 9 12-6 12-5 46-5 42-5 41-5 30-5 15- 3 16- 7 13-8 6-5 16-5 16 17 20 14 8-6 6-7 Hive No. 2. Difference. J Excited. Difference, j o o o 74-2 o ! 7.5-2 63-5 72-3 20-9 45-3 72 70 40-5 52-5 82-2 32-2 51 16 13-1 6-8 21 56-5 53-5 42-6 152-3 55-3 45 91 93 84-4 102 67-5 Remarks. Bees more quiet but readily excited. Bees quiet. Slightly active; soil bard frozen in the shade. TBees excited by the slightest noise, although entirely undisturbed for the last nine days, during four of -< which the temperature of atmosphere has been below 32°, sometimes so low as 24° Fahr. Bees L raised the thermometer to 72°-3 in ten minutes. Bees quiet ; soil still hard frozen. Bees quiet, but excitable ; intense hoary frost. Frost during thenight; temperature rising; bees quiet. Bees quiet; a gentle thaw. Bees quiet. Bees quiet. Bees quiet. Quiet, but excitable; frost, with wind and sleet all day. Day-break; starlight; hive excited; temperature raised in 16 minutes, and maintained for several minutes at 70° Fahr., but at 5 inches distant from this part of hive, temperature only 45°, thus giving a temperature of 25° for the bodies of the bees. Very fine. Hive more quiet; very fine. Only very faint sounds in the hive. J Hive quiet; wind shifting ; temperature rising ra- 1 pidlv. Bees irritable; wind shifting. Hive quiet. Hive quiet; frost broke suddenly, f Bees undisturbed for three days; excited tempera- < ture continued at 70° for several hours; many [ bees going abroad. J On the 15th inst., a very fine day, I saw' many bees \ enter the hive with orange, brown and grey pollen. Fine day. Hive quiet; hard frost all night. Hive No. 2. very active; light clouds. Calm cold morning. Bees go abroad but return quickly ; air too cold. Table XIV., showing- the Difference between the Temperature of the Atmosphere and that of the same Hive at half- hourly observations, made at precisely the same periods in succeeding- years, 1836 and 1837. MR. NEWPORT ON THE TEMPERATURE OF INSECTS 333 334 MR. NEWPORT ON THE TEMPERATURE OF INSECTS. Table XV. Showing the Temperature of the Atmosphere and of the Bee Hives No. 1 and No. 2 every fifteen minutes during thirteen successive hours on the 2nd April, 1837, and of Hive No. 1 on the same day in April, 1836. 1837. 1836. Remarks on the Hives and Weather, 183/. No. of Exp. | Period of observa- tion. Wind. a < g- O > s O O g 1 5 04 o’ £ O > s 0) O O £ 5 Wind. 0 S g- 6 £ O > s O O C O u Sa 3 1837. 0 0 0 0 0 O 0 O 1 Calm N.W.N. 26-2 53-5 27-3 52-8 26-6 2 Calm N.W.N. 26-2 53-5 27-3 52-2 26 3 A.M. 64 Calm N.W.N. 27-6 54-4 26-8 54 26-4 High N.W 35 59 24 Slight humming ; stratified clouds in the west. 4 A.M. 6f Calm N.W.N. 29-3 54-4 25-1 54-8 25-5 High N.W 36 61 25 Slight humming in both hives. 5 a.ji. 7 Light N.W.N. 33 54-5 21-5 57-6 24-6 High N.W 36-8 59 22-2 Very fine; clouds fleecy. 6 Light N.W.N. 33-5 54-6 21-1 59 25-5 7 A.M. 7\ Light N.N.W. 35-7 56-3 20-6 60-3 24-6 High N.W 38-5 58-9 20-4 Both hives quiet; very fine morning. 8 LLht N.N.W. 36-9 57-6 20-7 60-8 23-9 9 A.M. 8 Light N.N.W. 38-5 56-7 18-2 60-7 22-2 High N.W 39-5 61-1 21-6 Hives still quiet. 10 Light N.N.W. 42 57-6 15-6 64 2 2 11 A.M. 85 Light N.N.W. 43-2 59-5 16-3 63-8 20-6 High N.W 41 60-5 19-5 Not a bee has yet gone abroad. 12 Light N.N.W. 44-3 59-6 15-3 63-2 18-9 13 A.M. 9 Light N.N.W. 45-7 60-7 15 63-3 17-6 High N.W 42 60-3 18-3 Very fine ; fleecy clouds in the west. 14 Light N 47-2 61-7 14-5 64-3 171 15 LiUn N 47-6 63-7 16-1 67-3 19-7 16 A.M. Light N 4.9-3* 64-7 15-4 67 17-7 Sky fleecy; two or three more bees abroad. 17 A.M. 10 Light N 50‘4 65-4 15 69-1 18-7 High N.W 44 61-3 17 First bee just returned with pollen. 18 Light N 49’5 66-5 17 75-6 26-1 Three more bees have returned with pollen . 19 50-5 69-2 18-7 76-1 25-6 High N W 44*5 61-4 16-9 20 Light N 49-5 70 20-5 77 27-5 Many bees returning with pollen. 21 A.M. 11 Light N 48-3 73-9 25-6 78-3 30 22 Light N 47 72-7 25-7 80 33 Fine bright clouds; bees irritable. 23 A.M. 11^ Light N. by E. 45-6 72-6 27 79 33-4 Very fine ; pollen collected. 24 A.M. U| Light N. by E. 45 74 29 78-2 33-2 Very fine; hives active. 25 Light N 46 73-8 27-8 78-6 32-6 Seven loaded bees return per minute. 26 A.M. 12| LightN.by W. 47-5 73-6 26-1 79-3 31-8 Wind shifting ; much pollen collected. 27 Noon 124 Light N.N.W. 45-2 74-4 29-2 79 33-8 High N.W.W. 48 64-7 16-7 Fourteen loaded bees return per minute. 28 p.m. 12| Light N.N.W. 45'6 75-3 29-7 78-8 33-2 Sky fleecy ; few bees going abroad ; many returning. 29 r.M. 1 Light N.N.W. 49-2 75-3 26-1 82-7 33-5 Ten loaded bees per minute. 30 P.M. 1 4 Bride N.N.W. 48-9 74-6 25-7 81 32-1 Bees fighting at entrance of the hive. 31 P.M. 14 Light W 48-2! 74-6 26-4 81 32-8 High N.W.W. 48 62-8 14-8 Fair ; bees flocking home hastily ; few go abroad. 32 P.M. 1| Light W. by S. 47-7| 75-9 28-2 78 30-3 Rather overcast; very few bees abroad. 33 P.M. 2 Brisk W.S.' ... 47-7, 75-3 27-6 74 26-3 Overcast; scarcely a bee goes abroad. 34 P.M. 2| Brisk W.S. ... 47-5 74-4 26-9 75 27'5 Dull ; cold wind. 35 r.M. 24 Brisk W.S. ... 46-2 74-9 28-7 72 25-8 High N.W.W. 46-8 64 17-2 Dull ; not a bee abroad. 36 r.M. 2J Brisk W.S. ... 45-5 73-6 28-1 70 24-5 Dull ; slight humming in the hive. 37 p.m. 3 Brisk W.S. ... 45-3 74 28-7 68-2 22-9 High N.W.W. 44 65 2 21-2 Very dull ; signs of rain. 38 P.M. 31 Brisk W.S. ... 45-5 73-5 28 67-3 21’8 Very dull. 39 P.M. 3i Brisk W.S. ... 44-5 73-5 29 67 225 High N.W.W. 42-6 62-5 19-9 Very dull. 40 p.m. 34 Light S.W. ... 43-5 72 28-5 05 21 5 Very dull ; hives quiet. 41 P.M. 4 Light S 45-3 71-5 26-2 63-3 18 High N.W.W. 40-5 62 21-5 Fair. 42 r.M. 4* Light S 43-1 72 28-9 64-3 21‘2 Fair. 43 P.M. 44 Light S 42-5 71 28-5 64 21’5 Sunny, with clouds. 44 P.M. 4§ Light S 42-5 71 28-5 66 235 Dull; moist cool wind. 45 P.M. 5 Light S.W. ... 42-6 71 28-4 67 24-4 Biisk N.W.W. 41 60-3 19-3 Dull ; hazy. T.iodit W 41*8 (59-2 27-4 64 47 r.M. 5^ Light W 41-6 69- 27-1 63 21-4 Very dull. 48 P.M. 5f Light W 41-5 68-9 27-4 62-5 21 Dull. 49 P.M. 6 Light W 40-3 67-2 26-9 62- 21-7 Brisk N.W. ... 41 61-1 20-1 Dull ; hives quiet. 50 P.M. 6} Light W 40*5 67*1 26-6 62-8 22-3 Dull. 51 r.M. (}' Light W.S. ... 40-2 67-2 27 62 21-8 Dull. 52 P.M. 6| Light N.W.... 40 68 28 63 23 Dull. 53 P.M. 7 Light N 39 67-6 28-6 62-5 23-5 Brisk N.W. ... 40-3 61 20-7 Very much overcast; hives quiet. 54 P.M. 10 Calm 32 Very cloudy. MR. NEWPORT ON THE TEMPERATURE OF INSECTS. 335 Table XVI. Mean daily Temperature of the Atmosphere and Bee Hive No 1. as deduced from observations made at about the hours of seven, nine, and twelve in the morning1, and two and five in the afternoon, from October 23, 1835, to November 18, 1835 ; and of the Hives No. 1 and 2 from February 19, to September 30, 1836. 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 1835 Oct. 23 24 25 26 27 28 29 30 31 Wind. W. by S. Light .. S. IHigh .. W. by S. High .. W. by N. Light ... W. Calm ... S.W. Calm ... E. by S. i Light ... S.W. I Shifting Weather. Fine Cloudy .... Hard rain. Showery . Fine Faii- Mean temperature in October. Nov. 1 2 3 4 5 6 7 8 9 11 N.E. S.W. S.E. E. E. N.E. N.E. N.W. N.E. N.E. N. 12 N.E.N. N.E. N.E.N. N.E. 16jW. by N. 17 W. 1S| W. by S. Light .. Light ... Brisk ... Brisk ... Light ... Calm ... Shifting Brisk ... Brisk ... Calm ... Light ... Light ... Shifting Bleak ... Light ... Calm ... Brisk ... Fine Fair Misty rain . Showery Steady rain. Fine Fair Fine Cloudy Hazy rain ., Calm, fair . Cloudy Fair Misty rain . Cloudy 20 21 22 23 24 25 26 27 28 29 N.W. N.E.E. N.W. W. W. by S. S.W. W. N.E. W. w. w. Light Calm Light Light Light Light Brisk Light Light Light Light Fine Fine .... Fine .... Fine .... Light clouds .. Showery Fine Rain and sleet Cloudy Fair Fine Mean temperature in February 40-35 50-10 Mean temperature in November | 43-35 1836. Feb. 1!) March 1 I 4 5 1 6 7 8 9 12 13 14 15 16 17 18 19 20 21 S.S.E. W. W. W. S.W. 5.5. E. S.S E. N.N.E. S. by E. S.W. W. W. W. N.W. W. bv S. 5.5. W. E.S.E. W. S.W. Brisk Brisk L'gbt Light High High Light Light Shifting High Brisk High Tremendous Light High Light Light Light Light Rain, cloudy.. Fine Rain Fine Hard rain Continued rain Fair Cloudy Cloudy Rain Fair Rain Hard rain Fine Cloudy Fine Fine Hazy Misty rain 1 Atmo- sphere. 1 Hive No.l. — Difference. 1 Hive No. 2. Difference. J o o o o o .. 47-3 7 58-3 7 11 .. 52-8 j 60 0 1 7-2, i .. 47-5 [ 55-1 7-6 .. 49-48 55-5 5 6-0 8 .. 45-26 52-3 7-0- 1 .. 40-2 54-8- 14-6- 1 .. 54-33 60-31 6 48-1 57-3 9-2 .. 54-2^ l 65 -2( ) 10-91 .. 48-8( > 57-65 8-8; — 61-01 15-81 .. 48-l( 54-85 6-71 .. 46-3 53-85 7-5f .. 42-6/ 50-32 7-65 .. 44-15 49-57 5-42 .. 40-38 47-28 6-91J .. 47-88 61-5 13-62 .. 43-16 56-38 13-22 .. 41-16 49-14 7-98 . 38-03 44-21 6-23 . 41-62 44-42 2-80 38-34 44-66 6-32 . 3S-22 50-34 12-12 . 43-9 55-52 11-62 . 40-76 46-98 6-22 .44-96 47-04 2-08 .50-37 49-92 .[43-35 51-0 7-65 . 40-9 48-63 7-73 53-03 12-131 . 35-7 50-2 14-5 74-13 38-43: . 38-3 51-1 12-8 60-26 21-96 . 43 07 50 6-93 58-47 15-40 . 43 50-1 7-1 54-86 11-86 . 42-6 50-7 8-1 56-16 13-56 . 42-3 54-4 12-1 60-7 18-4 38-9 49-47 10-57 54-25 15-35 39- 48-22 9-22 53-98 14-98 39-82 48-37 8-55 54-72 14-90 40-26 49-96 9-70 55-15 14-89 40-35 50-10 9-75 57-79 17-44 45-66 54-8 9-14 61-5 15-84 45-4 52-4 7 58-73 13-33 46-08 55-8 9-72 59-18 13-10 47-2 58-48 11-28 58-74 11-54 46 53-54 7-54 61-92 15-92 47-6 55-12 7-52 57-67 10-07 44-6 53-01 8-44 55-2 1 1 -60 40-03 50-2 1017 55- 14-97 37-93 47-6 9-67 51-83 13-90 47-6 55-7 8-1 47-48 57-26 9-78 49-3 58-4 9-1 50 57-1 71 4317 51-97 8-80 49-5 55-3 5-8 53-34 65-5 1216 1 54-64 71-6 16-96 1 49-36: 65-46 16-10 1 48-14 63-04J 14-90 Remarks. Bees active. Pollen collected in the morning. Pollen collected in the morning. Scarcely a bee abroad. A few bees abroad. A few bees abroad. Pollen collected ; m,.ny bees abroad. Much pollen collected in the morning. Pollen scanty ; many bees abroad. Pollen scarce ; many bees abroad. H ive quiet ; but a few bees abroad. No bees abroad. Hive quiet ; no bees abroad. Hive quiet. A few bees abroad; a little pollen collected. A little pollen collected ; bees disturbed. Many bees abroad. Cold bleak wind ; hive quiet. Hive quiet ; a little sleet this morning. A few bees abroad, but return quickly. No bees abroad. Bees greatly disturbed. Hive nearly quiet. Hive quiet. Clouds and light wind. A few bees go abroad, Pollen was collected on the 15th inst. Bees in No. 2 much disturbed. Many bees go abroad, but soon return. Pollen again collected. Pollen coTected ; bees fighting. [diarrhoea. Pollen collected; bees of No; 1. fighting; have Pollen collected. Hives quiet; rain, sleet, snow, and wind. Hives quiet. Hives less quiet ; no bees abroad. Pollen collected, bees fighting, have diarrhoea. [diarrhoea. Hives quiet ; bees disposed to come abroad; Many bees abroad fighting. Bees abroad ; only one returned with pollen. i collected ; many bees abroad. MR. NEWPORT ON THE TEMPERATURE OF INSECTS 336 Table XVI. (Continued.) No. of eJ Period of 8 j observation. | Prevailing. 57 1836. Mar. 22 S.AV.S. 58 23 S.S.W. 59 21 AV. 60 25 S.AV. 61 26 VV.N.AV. 62 27 S.S.E. 63 28 S.AV. 64 29 AV. 65 30 S.AV. 66 31 W. 7 97 98 99 100 101 102 103 104 105 106 107 108 109 April 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 1G 17 18 19 20 21 22 23 24 25 26 2 28 29 30 May 1 Wind. Weather. Var. light... Light Brisk Brisk High Brisk Var. high... High Var. high... High Clouds and rain Clouds, rain ... Very fine Stormy Fine Mean temperature in March. N.E.E. N.W.W. N.W. N.N.W. s.s.w. S.E. S. W. S.W.S. S.W. S.E. ST. by W. S.W. s.w. s. S.E. S.E. S.W.S. AV. w. w. AV. S.W. S. AV. s. N.E. N. N.E. N. N. E. by N. High High High Light Light Var, light.., Brisk High Light Var. light.. Light Brisk Brisk Var. light.. Light Light Var. calm.. Light Calm Brisk Light High Brisk Calm Light Light Var. brisk.. Light High Var. light.. Rain and snow Cloudy Stormy Very fine Fine .’ Fair Sunny Cloudy Fair Showery Light clouds . Fair Fair Dull Fair Fine Light rain Light rain Fine Fair Fine Very fine Rain and fair .. Steady rain Fine Fine Fair Cloudy .. Fair Fine Mean temperature in April N. E. N.E.N. N.E. E. E. E. E. by S. N.E. E. AV. W. AV. High Tremendous. Very high Brisk Light Light Light Brisk Light Brisk Light Light Light Fair Hard rain Fine Fine Showery .. Very fine.. Very fine.. Very fine.. Very fine.. Fine Very fine.. Arery fine.. Very fine.. ii <*§< 6 5Z Q > s Difference. | Hive No. 2.1 O v S u &£ S o o o o o 48-7 62-82 14-12 47-4 62-28 14-88 44-72 59-52 14-80 51-3 67-6 16-3 42-64 60-64 18 46-3 61-84 15-54 43-8 62-6 18-8 46-16 60-8 14-64 49-8 63-8 14 47-2 54-9 7-7 46-93 58-59 11-66 57-75 10-82 41-5 59-5 18 42-9 61-66 18-76 48-75 63-05 14-30 45-9 72-3 26-4 48-66 71-44 22-78 97-3 48-64 45-9 71-2 25-3 67-3 21-4 51-76 72-03 20-27 68-06 16-30 47-5 682 20-7 65-27 17-77 49 69-54 20-54 67-16 18-16 50-56 73-44 22-8.8 71-42 20-86 51-46 72-68 21-22 72-42 20-96 48-42 69-75 21-33 69-87 21-45 52-06 72-84 20-78 72-54 20-48 51-45 73-5 22-05 73-75 22-30 57-76 76-72 18.96 81-6 23-84 54-42 76-26 21-84 85-86 31-44 . 47-26 74-66 27-40 76-98 29-72 . 49-06 78-78 29-72 77-34 28-28 . 50-72 74-77 24-05 79-62 28-90 . 53-3 75-9 22-6 85-55 32-25 . 51-2 73-46 22-26 86-7 35-5 . 54-88 76-74 21-86 86-8 31-92 . 51-98 75-26 23-28 85-52 33-54 . 48-6 75 26-4 79-5 30-9 77-2 22-78 81-5 27-08 81-65 26-43 82-2 26-98 . 48-5 78-75 30-25 79-62 31-12 . 47-25 74-4 26-15 80-9 32-65 75 -8r 26-47 80-93 31-57 75-62 26-36 OO W 28-74 . 49-93 73-07 23-14 78-22 28-29 . 55-3 79-65 24-35 81-65 26-35 . 471 74-16 27-06 76-53 29-43 . 53-25 77-7 24-45 79-27 26-02 . 55-67 80-5 24-83 83-57 27-90 . 50-36 84-54 34-18 83-5 33-14 . 56-67 84-12 27-45 87-87 31-20 . 59-74 85-26 25-52 91-42 31-68 . 57-54 83-5 25-96 91-7 34-16 . 57-84 82 24-16 92-28 34-34 . 57-92 83-16 25-24 89-66 31-74 . 57-78 81-92 24-14 89-22 31-44 . 51-8 87-16 35-36; 91-66 39-86 . 66-98 87-06 20-08: 96-17 29-19 Remarks. Scarcely a bee abroad ; no pollen collected. Pollen collected in the morning. Bees active; much orange and yellow pollen. Pollen collected ; bees very active. No bees abroad ; rain and hail. Pollen, orange and yellow, collected. No bees abroad ; hive quiet. But few bees abroad ; no pollen. Hive quiet ; weather tempestuous. Scarlet and orange pollen collected; many bees abroad. ("Mean temperature of No. 2, in the first nine days of \ March. No bees abroad; hard continued rain with snow. A few bees abroad with pollen. Many bees abroad perished with the wind. Orange and yellow pollen in abundance. Pollen in abundance; Hive No. 2 much disturbed. But few bees abroad ; cloudy, fair. Pollen, scarlet, orange, and yellow in abundance. No pollen collected ; few bees abroad. Pollen in abundance, scarlet, white, yellow, brown. Pollen abundant, orange, yellow, scarlet, grey, volute, brown. Pollen abundant, orange, yellow, scarlet, grey, white. Few bees abroad; signs of rain. Bees very busy ; pollen orange, scarlet, yellow, grey. Bees very busy ; damp atmosphere. Signs of rain ; bees still very active. Pollen in abundance, scarlet, orange, grey, yellow, brown. A few bees abroad. A few bees abroad, no pollen collected. Pollen in abundance, yellow, white, grey, orange, scarlet. Bees very active ; working. Many bees abroad ; working. Pollen in abundance, chiefly dirty white and orange. But few bees abroad ; showery. Very few bees abroad. Bees very active ; working. Many bees abroad ; pollen abundant. Few bees abroad. Few bees abroad. Pollen nearly all deep orange ; a fall of snow this morning. j Thick ice this morning; abundance of pollen, chiefly deep orange. Many bees abroad ; pollen abundant. Snow this morning ; rain all day. Abundance of pollen, orange and scarlet. Abundance of pollen, orange and white. Many bees abroad. Great commotion in the hives; young bees hatching. Abundance of pollen, scarlet, yellow, brown, grey, orange. Many bees abroad; working. Bees very active. Drone bees have just appeared. Hoar frost last night; pollen collected. Many drones abroad ; bees active. Drones abroad ; bees beginning to lay out for swarming, MR. NEWPORT ON THE TEMPERATURE OF INSECTS. 337 Table XVI. (Continued.) ?T w o d fc Period of 8 observation. J ( Prevailing. i Wind. Weather. Atmo- sphere. Hive No. 1. Difference. 1836. o o no May 14 N.byE. Calm ... Very fine 68-36 87-36 19 in 15 N. Light ... Very fine 66-74 89-48 22-74 112 16 S. Var. light Fine 67-52 88-8 21-28 113 17 E. Light ... Very fine 65-4 89-28 23-88 114 18 S.E. Light ... Very fine 71-06 93-9 22-84 115 19 E. Light ... Light clouds 67-74 92-8 25-06 116 20 S.E. Light ... Very fine 67-54 94-04 26-50 117 21 E. Light ... Dull day 61-17 95-37 34-20 118 22 E. Brisk ... Fine 61-77 92-83 31-06 119 23 E. Brisk ... Dull day 52-75 88-41 35-66 120 24 N.E. Light ... Fair 59-75 88-45 28-70 121 25 N.E. Light ... Fair 57-08 86-7 29-62 122 27 E. Brisk ... Fine 63-03 92-43 29-40 Temperature of No. 2 up to period of swarming 123 28 E. Light ... Fair 50-04 90-28 40-24 124 29 N.E. Light ... Very fine 63-5 89-75 26-25 125 30 N.E. Light ... Fine 65-12 90-1 24-98 126 31 N.E. Light ... Fine 68-8 91-72 22-92 Mean temperature in May Total mean temperature of four months'! before swarming f 127 June 1 N.E. Light ... Showery 60-37 87-7 27-33 128 2 N.E. Shifting Rain 56-02 84-37 28-35 129 3 s.s.w. High ... Rain 51-7 87"25 35-55 130 4 s.s.w. High ... Fair 60-5 86-16 25-66 131 5 s.w.w. Brisk ... Dull 61-8 86 24-2 132 6 s.w. High ... Fine 63-37 90 26-63 133 7 s. Brisk ... Fine 58-4 89-15 30-75 134 8 s. Brisk ... Rain 61 -85 90-5 28-65 135 9 s. Light ... Dull 62-5 91-5 29 136 11 s.w. High ... Fair 65-75 90-7 24-95 137 12 s. w. High ... Very fine 64-6 88-37 23-77 138 13 s.w. Light ... Very fine 70-6 94-83 24-23 139 14 N.E. Var. light Very fine 71-2 92-24 21-04 140 15 E. Light ... Fair 73-64 92-14 18-50 141 16 W. Light ... Fine 65-12 88-84 23-72 142 17 E. Light ... Fine 66-22 90-38 24-16 143 18 S.W. Brisk ... Very fine 66-04 87-17 21-13 144 19 w. Light ... Fine 64-4 86-43 22-03 145 20 w. Light ... Very fine 65-82 89-37 23-55 Mean temperature in June 63-67 *89-11 25-44 146 July 20 w. Light ... Fair 58-32 78-65 20-33 147 21 w. Light ... Showery 62 78 16 148 22 w. Light ... Showery 60-98 80-33 20-35 149 23 s.w. Var. light Fair 63-96 84-14 20-18 150 24 s.w. Light ... Fair 63-92 79-47 15-55 151 25 w. Light ... Light clouds 67 78-15 11-15 152 26 w. Light ... Very fine 68-15 80-15 12 153 27 w. Brisk ... Dull 63 79 16 154 28 E. by S. Light ... Fine 65-8 80-1 14-3 Mean temperature in July 63-68 79-77 16-09 155 Aug. 2 W. light ... Very fine 65-47 75-1 9-63 156 4 S. Light ... Fair 67-78 81-2 13-47 157 5 S. Light ... Rai n 66-1 81-79 15-69 158 7 S.E. Light ... Very fine 70-83 81-03 10-20 159 8 S.E. Light ... Fine 69-16 79 36 10-20 160 12 S.E.E. Light ... Fine 71-75 81-15 9-40 60-17 49-34 92- 82 90-94 96-06 93- 98 95-5 93- 22 94- 36 93-7 92-83 88 90- 2 91- 8 93 90-06 87-08, 26-91 67-21 17-87 86-24 91- 75 90-75 92- 4 90-06 70-95 90-1 86-4 88- 7 85-16 88 89- 45 89-8 89 85- 95 86- 95 93 90- 16 91- 94 88- 32 89- 54 82-66 83- 56 84- 75 -f-87-96 24-46 24-20 28-54 28- 58 24- 44 25- 48 26- 82 32-53 31-06 35-25 30-45 34-72 29- 97 Remarks. 29-89 36-20 28-25 25-63 24-6 29-89 21-61 20-20 22-35 22- 4 18-96 18- 30 23- 20 23-32 16-62 19- 16 18-93 24-29 Bees hanging out; loud humming in the hives. Hive No. 2 lifted to prevent swarming. Suneclipsed at2p.M Bees hanging out, much excited; hive replaced. Bees hanging out ; drones abroad. Bees hanging out. No bees hanging out, except a few in the morning. Bees again hanging out. Bees still hanging out. No bees hanging out ; very few abroad. No bees hanging out; very few abroad. Many bees abroad, but not hanging out. Many bees abroad, but not hanging out. Hive No. 2 swarmed suddenly at 24 r.M. f A dead drone and queen nymph thrown out from the! [ swarmed Hive No. 2. Very few bees at entrance of Hive No. 2. Three queen nymphs ejected from Hive No. 2. Abundance of pollen brought home. s Bees of both hives very busy. Bees abroad in the morning. Bees very active. Few bees abroad. Signs of rain ; few bees abroad. Many bees abroad. Many bees abroad. Bees of No. 1 working in the side box. Working in side box ; many abroad. Bees very busy ; (many bees at entrance of Hive No. Symptoms of swarming again in Hive No. 2. Bees much agitated at entrance of No. 2. Loud sounds in both hives ; pollen abundant. Evening showery, and bees hanging out again from No Evening stormy, with thunder; bees hanging out. Evening stormy ; bees hanging out. Second swarm left Hive No. 2 at 7 a.m. Showery; Hive No. 2 very thin. Temperature of Hive 2 reduced. Has rained hard for thirty-six hours; bees active. Bees very active ; pollen black. Many bees abroad ; no drones have yet been killed. Bees in No. 1 disturbed. Killing drones in the first swarm from No. 2. Bees very active. Many bees abroad. Massacre of drones in the swarm continues. Bees verv active. Attacking the drones in second swarm from No. 2. Bees very active; light rain and clouds. Bees very active ; light rain. Heavy dew last night. Bees disturbed. Massacre of drones continues. 1.) * Mean temperature in June of No. 1, the unswarmed hive, f Mean temperature of Hive 2, in June, after twice swarming. 338 MR. NEWPORT ON THE TEMPERATURE OF INSECTS Table XVI. (Continued.) No. of Exp. 1 Period of observation. Prevailing. Wind. Weather. 1836. 161 Aug. 12 E. Light ... Very fine 162 14 S. by E. Light ... Very fine 163 15 W. Light ... Fair 164 16 S.E.E. Light ... Very fine 165 17 s.w. Brisk ... Very fine 166 18 w. Brisk ... Dull 167 19 N.W. Light ... Fine 168 20 N.W. High ... Hard rain ... 169 21 N.W. Brisk ... Fine 170 22 S.W. High ... Fair 171 23 S.E. Light ... Rain 172 24 N.E. High ... Fair 173 25 S. Light ... Fine 174 26 S.W. High ... Dull 175 27 s. w. ■High ... Fine 176 28 s. w. Light ... Showery 177 29 N. Calm ... Very fine 178 30 w. Light ... Light clouds 179 31 s.s.w. Light ... Very fine Mean temperature in August 180 Sept. 1 S.W. Brisk ... Fine 181 2 W. Brisk ... Light clouds 182 3 S.S.W. Light ... Fine 183 4 S. Brisk ... Showery 1S4 5 w. Brisk ... Light clouds 185 6 w. High ... Rain 186 7 N. Light ... Very fine 187 8 N. Light ... Fine 188 9 S.W. Light ... Showery 189 10 w. Brisk ... Stormy 190 11 N.W. Brisk ... Fine 191 12 N. High ... Fine 192 13 N. High ... Fair 193 14 N.N.E. Light ... Fair 194 15 E. Brisk ... Fine 195 16 N.E. Brisk ... Fine 196 17 N.W. Light ... Fair 197 19 N. Light ... Fair 198 21 N. Calm ... Dull 199 22 S. Light ... Dull 200 23 w. High ... Hard rain ... 201 24 w. Brisk ... Very fine 202 25 S.W. Light ... Fine 203 26 s. Brisk ... Dull 204 27 s.w. Light ... Dull 205 28 S.W.W. High ... Showery 206 29 s.w. High ... Rain 207 30 N.W. Light ... Fine Mean temperature in September , Total mean temperature of four months after 1 swarming J Total mean temperature of the periods before 1 and after swarming ...’ J £2 < &■ 76- 4 77- 45 71-64 70- 06 71- 57 63- 98 69-12 59- 05 64- 9 66-62 63-38 60- 64 63-22 68-56 65- 16 65-15 67-3 67- 3 68- 7 67-64 66- 14 59-58 63-02 67- 05 59- 18 56- 03 57- 07 60- 92 57-23 56-02 56- 86 57- 84 58- 66 57- 47 58- 75 57-5 60-67 63- 87 57- 4 55-73 60- 83 66-18 64- 65 63-46 66-06 61- 3 53-1 58- 76 60-04 63-75 56-54 81-1 82- 9 84-24 83- 58 80-92 78-74 78-52 73- 31 75-1 74- 92 73- 26 74- 88 74- 32 75- 23 73- 14 76- 57 74- 82 74.82 74-86 4- 7 5- 45 12-60 13- 52 9-35 14- 76 9-40 14-26 10-2 8- 30 9- 88 14-24 11-10 6- 67 7- 98 11-42 7-52 7-52 6-16 77-79 10-15 76-64 71-08 69-02 72 69-89 64-5 66- 3 67- 87 67- 6 64-46 61-02 64-46 64-8 64-82 63- 45 66 68- 03 69- 20 61 58-26 66- 43 68- 64 69- 45 69-78 69-1 64- 93 55-7 67- 83 66-5 78-29 72-75 10- 50 11- 50 6 4-95 10-71 7- 47 9-23 6-95 10-37 8- 44 4-16 6-62 6- 14 7- 35 4- 70 8- 5 7-36 5- 33 3- 6 2-53 5- 60 2- 46 4- 80 6- 32 3- 04 3-63 2-6 9- 07 74-32 83-75 74- 62 80-93 76-37 75- 28 75- 28 74-87 74- 63 76- 26 78 78-5 78-5 75- 3 6-46 14-54 16-21 76;9 73-22 72-96 72- 45 73- 4 70 67-86 69-3 69- 77 65- 66 66- 66 67- 54 66-62 68- 08 68-1 67- 82 68- 8 70- 1 70-38 65-7 62-02 67-76 72-96 70 -7 70- 94 71- 4 65-53 57-03 69-2 10- 34 14- 63 15- 57 16- 03 9-75 11- 90 15-64 1T65 6-07 11- io 12- 85 11-2 11-2 6-6 Remarks. 10-82 66-68 77-18 74-06 7- 08 13-38 9-43 6-35 10-82 11- 83 12- 23 8- 85 8-43 10-64 10-68 8- 78 9- 42 10- 63 9-07 11- 3 10-43 6-51 8-3 6-29 6-93 6-78 6- 05 7- 48 4-34 4-23 3-93 10-44 6-64 13-43 Bees abroad in great numbers. Abundance of pollen, white , orange, brown, green, and grey Still killing the drones in the young swarms. Beginning to kill the drones in Hive No. 1. Pollen in abundance; killing drones. Loud sounds in the hive; few bees abroad. Bees very active. Three nymphs expelled from No. 2. Three nymphs ejected from the first swarm from No. 2. A drone turned out from swarm. Bees very active. Few bees abroad ; drones have all perished. Few bees abroad. Few bees abroad. Few bees abroad. Abundance of bees abroad with pollen. Many bees abroad with orange pollen. Bees very active. Abundance of pollen, yellow, orange, grey. Much pollen collected, orange, grey, yellow, and brown. Pollen less abundant ; showery. Pollen collected from the mignionette. Not many bees abroad ; showery. Fine, but windy. A cold rainy day, with wind. Many bees abroad, working. A little showery, with light wind. Hard rain all the morning. Bees abroad at noon ; weather rough. Cold wind, but fine; few bees abroad. Not many bees abroad. Signs of rain; hives quiet. Signs of rain. Bees abroad. Weather unsettled ; showery. A few bees abroad. Weather unsettled. Bees still abroad. Hives quiet ; no bees abroad. Hives quiet ; hard rain to-day. Great commotion at the entrance of the hives. Fair ; many bees abroad. A few bees abroad. No bees abroad. Fair, windy; a few bees abroad. Hives quiet; rain and wind all day. Bees abroad again. 17-52 yy^z^^JiDcccxmnLT’toxyi.^. 339 , Jc ^/ /l/ 'rt.l/'s// , /. ///'tsztZcrrv, K%cr/i-eu). [ 339 ] XVIII. On the first Changes in the Ova of the Mammifera in consequence of Impregna- tion, and on the Mode of Origin of the Chorion. By Thomas Wharton Jones, Esq. Communicated by Richard Owen, Esq. F.R.S. Received March 16, — Read April 27, 1837. Part I. — On the Changes in the Envelopes. HAVING previously described the structure of the ovum of mammiferous animals, as it exists in the ovary before impregnation*, I now proceed to relate some facts re- specting the changes which it undergoes in consequence of that act. My observations in reference to this point are the following. Observation 1. — On Wednesday the 16th, and Thursday the 17th September, ]835, I examined the internal organs of generation of a Rabbit, which had been impreg- nated on the afternoon of the Saturday preceding, and which was killed on the after- noon of Tuesday. The ovaries of both sides presented corpora lutea. In the Fallopian tube of the right side, near where it enters the horn of the uterus, I found six ova. Iti the same place on the left side there were only two. They dif- fered very remarkably from the ova as they exist in the ovaries before impregnation, inasmuch as the former presented, in addition to the component parts of the ovum of the ovary, a thick gelatinous matter surrounding it, similar to what is observed in the ovum of the Frog. The addition of this gelatinous envelope made the diameter of the whole body about Tvth of an inch. Plate XVI. fig. 1. represents one of these ova magnified 40 diameters, and fig. 2. the ovum of the Frog when recently laid, magnified 2 diameters. I could not detect the germinal vesicle in the ova in question. The granulary matter of the yelk was coherent. The application of weak vinegar to the ova ren- dered the yelk transparent. Dilute nitric acid made the superadded gelatinous en- velope contract, but by the addition of more water it gradually expanded again. The question which this observation suggests is, “ Where do the ova acquire the additional gelatinous envelope; in the Fallopian tubes or in the ovaries?” The two following observations give the answer, “ In the ovaries.” Observation 2. — March 6, 1236. Examined a female Rabbit to-day, 41 hours and 40 minutes after impregnation. There were no ova in the horns of the uterus, nor in the Fallopian tubes. The right ovary presented on its surface a very large and prominent Graafian ve- * See Lond. and Edin. Phil. Mag. vol. vii. p. 209. 2 Y MDCCCXXXVII. 340 MR. JONES ON THE IMPREGNATED MAMMIFEROUS OVUM. side, quite transparent, except at its most projecting point, where there was a spot of blood. I perceived nothing peculiar in the ovum contained in this vesicle. I did not detect a germinal vesicle in it. Besides this large and prominent Graafian vesicle there were on the surface of the right ovary other five prominent vesicles filled with coagulated blood. At the most projecting point of each of these there was a small whitish mammillary elevation, within which was contained the ovum, surrounded by a transparent gelatinous sub- stance, the same as that described in the preceding observation ; only it is to be re- marked, that in the Fallopian tubes this gelatinous looking substance had swelled out and acquired a greater diameter than it presented in the ovary. I did not detect a germinal vesicle in the ova forming the subject of this observation. In the left ovary I found only one vesicle, containing the coagulated blood and the ovum surrounded by the gelatinous looking envelope. Observation 3. — A Rabbit 48 hours after impregnation presented appearances much the same as the above. Is any trace of the gelatinous looking envelope of the ovum to be observed before impregnation ? In the ova of the Rabbit, &c., before impregnation, the proligerous disc, in which the ovum is imbedded, is observed to be composed of a gelatinous substance interspersed with grains, but as yet there appears no distinctly circum- scribed envelope*. The gelatinous looking envelope of the ovum I have just described must not be confounded with the vitellary membrane of the ovum, which was fully considered in my former paper. The former appears to be analogous to the cortical membrane surrounding the ovum of the Ornithorhynchus paradoxus , &c. while still in the ovary, described by Mr. OwEN'f'. That it, and not the vitellary membrane, as I formerly imagined, forms the chorion, will be made evident by the following observations. I would, however, premise some remarks on the ova of the batrachian reptiles, in order to place in a more striking point of view the circumstances I am about to re- late in regard to the ova of the mammifera. Fig. 2. exhibits the ovum of the Frog magnified 2 diameters. It is composed of a yelk, black on its surface, and whitish inside. The yelk is surrounded by a vitellary membrane, thicker than that of the bird’s egg, but thinner in proportion than that of the ova of the mammifera. Outside the vitellary membrane is a gelatinous envelope, which is added in the oviduct, the two preceding parts being formed in the ovary. When the ova are laid the gelatinous envelope rapidly absorbs water, and swells out to great thickness. * Dr. Karl Krause of Gottingen, however, in a late Number of Muller’s Archiv., speaks as if the gela- tinous substance really formed a well defined envelope. From his observations on the ovum before impregna- tion he has been led to form much the same opinion regarding the origin of the chorion as is recorded in this memoir. f Philosophical Transactions, 1834, p. 561. MR. JONES ON THE IMPREGNATED MAMMIFEROUS OVUM. 341 The ovum of the Newt differs from that of the Frog, inasmuch as the gelatinous- like matter which surrounds the yelk and its membrane is of an oval form, and is somewhat hardened on the surface, so as to form a kind of shell, inside which is a fluid substance, in which the yelk and its membrane can freely revolve and glide from one end to the other. The vitellary membrane is thinner in the Newt than in the Frog. Fig. 3. is the ovum of a Newt, in which development has commenced ; magnified rather more than twice. But what I wish particularly to insist on, in regard to the ova of the batrachian reptiles, and especially of the Newt, is, that when the embryo of the latter has attained a certain size, but still at an early period, the vitellary membrane gives way, and then the embryo is only contained within the cavity of the substance, which is added to the ovum in the oviduct, fig. 4. In the case of the Frog the vitellary membrane does not give way, until about the time the Tadpole is ready to burst all its envelopes. With the development of the embryo the cavity circumscribed by the vitellary membrane increases to as much as one fifth of an inch in diameter, and always retains its spherical form. There is a limpid fluid in the interior of the vitellary membrane, which seems to serve the pur- pose of an amniotic fluid, fig. 5. Observation 4. — March 18 and 19, 1836. Examined a female Rabbit seven days after impregnation. The right ovary presented four corpora lutea, the left ovary two. I found only one ovum in each horn of the uterus ; they were about -'o4ti of an inch in diameter*. Fig. 6, magnified 40 diameters. No vitellary membrane was to be seen. The gelatinous-looking envelope consti- tuted the only covering of the yelk, which now formed a vesicular blastoderma. The cavity of the gelatinous-looking envelope was much larger than the vesicular blasto- derma. The inner surface of the gelatinous coat presented what I supposed to be fragments of the vitellary membrane adhering to it. In both ova the vesicular blastoderma was irregular on one side, that on which I supposed the embryo was about to be developed. It was beginning to present the separation into layers, and had the same peculiar friable globular structure as the blastoderma of the hen’s egg. Observation 5.— This observation, which refers to the human ovum, agrees with that just related in regard to the ovum of the Rabbit. In the spring of 1836 I examined a small human ovum sent to me to Cork, where I then was, from Glasgow, by Dr. Mackenzie. In his letter to me, dated November 29, 1835, he describes it thus : “ A very small human ovum. It came along with the entire decidua from a patient of mine. It lay in the middle of one of the parietes of * The reason I found but two ova is, perhaps, that from their great transparency they may have escaped notice. The gelatinous coat was so transparent that I could with difficulty see the outline of it under the glass when it was observed by transmitted light. The vesicular blastoderma being opaque was the only cir- cumstance that enabled me to detect the ova at all. 2 Y 2 342 MR. JONES ON THE IMPREGNATED MAMMIFEROUS OVUM. the decidua, rather near its upper edge, and was about the size of a marrowfat pea, before being put into spirits. The decidua covering it, towards the hydroperionic cavity, was thin and semitransparent, but the opposite portion of the decidual nida- mentum was thick, and marked with foramina, as if from vessels which had pene- trated and adhered to it. Having opened the nidamentum and taken out the ovum, I observed what will immediately strike you, that one side of it was bald and the other shaggy with the villi of the chorion. The bald part lay towards the hydro- perionic cavity. A small puncture was made through the chorion, and perhaps through the amnion, by which some fluid escaped: nothing more was attempted. The Fal- lopian portions of the decidua measured nearly half an inch, and were both entire.” In a subsequent letter Dr. Mackenzie says, in reference to the age of this ovum, “ The ovum in question I consider as three or four weeks old. The lady had missed one menstrual period, and thought herself four weeks gone.” On laying open the ovum, by carefully cutting and reversing the bald side of the chorion, the following appearances (delineated, natural size, in fig. 7-) presented them- selves. The whole cavity of the chorion was filled with a fine gelatinous cellular tissue, imbedded in which, towards one extremity of the ovum, was a small round body. It was evidently the vesicular blastoderma; on being taken out and examined under the microscope it presented the same friable globular structure found in the vesicular blastoderma of the Rabbit in the preceding observation. There was no vitellary membrane to be seen. From observation 4. it may be inferred, that in the progress of the development of the ovum of the Rabbit the vitellary membrane gives way, as in the ova of the Newt and indeed of many of the oviparous animals ; that the gelatinous coat acquired by the ovum in the ovary, and more especially circumscribed and defined after impreg- nation, constitutes the only covering of the vesicular blastoderma after the giving way of the vitellary membrane ; that this gelatinous-looking coat forms the chorion, which in the rodents at a further stage of development presents itself under the form of a thin and transparent membrane, very like the vitellary membrane of the bird’s egg, situated immediately outside the non-vascular and reflected layer of the umbi- lical vesicle. The conclusions to be drawn regarding the human ovum from observation 5. are the same as the above. The human ovum as regards the vesicular blastoderma was in much the same stage as the ova of the Rabbit seven days after impregnation ; the vitellary membrane had disappeared, or been resolved into the gelatinous cellular tissue filling the interior of the chorion ; and the embryo had not yet appeared though the vesicular blastoderma was undergoing the preparatory changes. As regards the chorion, the human ovum was more developed than that of the Rabbit, but it is to be remarked that even in an after stage of development the same difference in structure continues to prevail. MR. JONES ON THE IMPREGNATED MAMMIFEROUS OVUM. 343 Appendix. I think it right to mention that in the Rabbit which formed the subject of observa- tion 1, I observed the following other points : Having cut off a piece from the ovarian extremity of the Fallopian tube of the right side, I put it into a glass capsule, and having laid it open, examined its contents with the microscope ; I observed among the numerous shreds of the lining mucous mem- brane a small body, transparent, and of a very peculiar shape. Having succeeded in transferring it from the capsule to a flat plate of glass, and having removed the shreds of membrane, I was enabled to examine it with a stronger power, and see better its very extraordinary form and structure, which are well represented in fig. 8. I had not a micrometer at the time to measure it, but I think it was about -^th of an inch in diameter at its globular extremity. The calculation was made by comparing it with an ovum from the ovary. It revolved through the water when the latter was put in motion, and in doing so the part a was forced to turn sometimes to the one side and sometimes to the other. In the next piece of the Fallopian tube of the same side which I examined, I found a transparent body not quite round, but prominent on one side, and close by the pro- minent point there was a small oval vesicular projection, fig. 9. There was an appear- ance of circular lines on it which touched each other at the prominent point ; three of the lines were particularly evident, and the prominent point had a brilliant appear- ance under the microscope. In the next piece of Fallopian tube examined I found a body, fig. 10, which on the whole resembled the preceding, but as I might say not so far developed. Could the three bodies described have been blighted ova ? They were all about -^Vth of an inch in diameter, and therefore corresponding in size to the real ova, already described as being found in the same Rabbit. Part II. — On the Changes in the Vitellus. What I have to communicate in this second part of my memoir is of a much less definite character than that which is given in the first part. From the nature of the subject it in many cases necessarily consists of inferences rather than observed facts. It relates chiefly to the ova of the batrachian reptiles, and is added here merely for the purpose of throwing some light on the changes which take place in the yelk of the ova of the mammifera, previously to the commencement of the evolution of the embryo. In approaching this subject the first question which presents itself is : “ When does the germinal vesicle of the ova of the mammifera disappear, before or after im- pregnation ?” It is known that in birds and reptiles the germinal vesicle disappears before impregnation. In the ova of the Frog, contained in the oviduct, and also in the more advanced of those contained in the ovary, no trace of the germinal vesicle 344 MR. JONES ON THE IMPREGNATED MAMMIFEROUS OVUM. is to be observed. The black blastoderma surrounds the whole yelk, with the excep- tion of a small spot* on the opposite side to that where the primitive streak appears. In the furthest advanced ova contained in the ovary of the Newt, the blastoderma was formed, and I think I perceived the place where the germinal vesicle had been. As to the ova of the inarnmifera, I have found many in which there was no germinal vesicle, and which certainly had not been impregnated. It is to be remarked that in such ova the vitelline grains were for the most part coherent and formed the vesi- cular blastoderma. It being determined that the disappearance of the germinal vesicle is prior to im- pregnation and not dependent on it, the next question which arises is “ how does the germinal vesicle disappear ?” My observations on the ova of the water Newt are the only ones I have which bear upon this question. From what I have observed in them I think the mode of disappearance is the following : The vesicle, at first imbedded in the substance of the yelk, approaches more and more the surface of it, until it comes to lie immediately underneath the vitellary membrane, in the manner represented in fig. 12. The coat of the vesicle having now become very soft and weak gives way, and the contained fluid is effused on the surrounding surface of the yelk. The coat of the vesicle being of extreme tenuity cannot be seen after it has given way. The small depression in which the vesicle was situate now forms the cicatricula, fig. 13. I think that the fluid contained in the germinal vesicle being effused gives a de- gree of consistence to the matter composing the surface of the yelk, and thus pro- motes the formation of the blastoderma. If then the germinal vesicle is not dependent on impregnation, it may be asked, what is the first change which takes place in the ova in consequence of impregnation ? Of all ova the ova of the Frog are those in which such change can be most directly observed. In them the breaking up of the surface of the yelk into crystalline forms, described by Prevost, and Dumas, is the first change I have seen. March 1 7 th, 1835. I examined to-day the spawn taken from a Frog yesterday, part of which was impregnated and part not ; that which was impregnated presented the appearance delineated in fig. 11. The unimpregnated ova presented no change The surface of the yelk becomes every day still more broken up, the crystalline forms becoming smaller and smaller, until the surface of the black blastoderma ap- pears under a magnifying glass like shagreen. The blastoderma, consisting of an aggregation of clear globules, different from those of the rest of the yelk, is now fully * This small spot of the ova of the frog which is white, (from the exposure of the white yelk,) always tutus to the most depending side. The germinal point is thus always uppermost. I turned a mass of spawn upside down ; the white spot was exhibited by all, but in a short time the white spot had turned downwards and the germinal surface again became uppermost. In this case, does the vitellus alone revolve, or does the vitellus and its membrane turn round together in the gelatinous substance surrounding the ovum ? It appeared to me that the latter was the way in which the revolution took place. ME. JONES ON THE IMPREGNATED MAMMIFEROUS OVUM. 345 formed ; it has extended itself so as to close in the white spot. Evolution then pro- ceeds. The change which takes place in the yelk of the bird’s egg appears to be limited to the neighbourhood of the cicatricula. In the ovum of the mammifera, there being little more than a blastoderma to be formed, the whole of the vitelline grains undergo a change, and are resolved into a vesicular blastoderma, presenting the same peculiar friable and globular texture as the blastoderma of the egg of the Newt, Frog, Bird, &c. The matter contained in the cavity of the yelk of the bird’s egg seems to be a sub- stance of the same nature as the blastoderma, and to serve for the extension of it. The blastoderma of the bird’s egg being once formed by the effusion of the fluid of the vesicle of Purkinge, and animated by fecundation, probably has the power to assimilate the matter in the cavity of the yelk to its own substance, without the assist- ance of a fluid such as that of the vesicle of Purkinge, which was first required to promote its formation. There is no central cavity in the ova of the Frog and Newt, because the blastoderma is formed at once all round the ovum. Description of the Plate. PLATE XVI. Fig. 1. An ovum found in the Fallopian tube of a Rabbit the third day after im- pregnation ; magnified forty diameters. Fig. 2. The ovum of the Frog when recently laid ; magnified two diameters. Fig. 3. The ovum of a water Newt in which development has commenced ; mag- nified rather more than twice. Fig. 4. A diagram showing the embryo of the Newt after the vitellary membrane has given way, contained only within the cavity of the substance which is added to the ovum in the oviduct. Fig. 5. A diagram showing the embryo of the Frog still surrounded by the vitellary membrane as well as the gelatinous substance tvhich is added to the ovum in the oviduct. Fig. 6. An ovum found in the horn of the uterus of a Rabbit seven days after im- pregnation ; magnified forty diameters. Fig. 7- A human ovum aborted at the third or fourth week ; natural size. Figs. 8, 9, 10. Bodies found in the right Fallopian tube of the Rabbit which forms the subject of observation 1 ; magnified about fourteen diameters. Fig. 11. This exhibits the breaking up into crystalline forms, observed on the sur- face of the Frog’s ovum after impregnation ; magnified about six diameters. Fig. 12, 13. Diagrams illustrating the mode of disappearance of the germinal vesicle. ' * | \ 1 [ 347 ] XIX. Sequel to an Essay on the Constitution of the Atmosphere , published in the Philosophical Transactions for 1826; with some Account of the Sulphurets of Lime . By John Dalton, D.C.L., F.R.S., 8$c. Received June 9, — Read June 15, 1837. In an essay of mine on the constitution of the atmosphere, which was printed in the Transactions for 1826, I signified my intention of following it with a sequel of experiments to ascertain if possible which of the two views therein developed was most countenanced by facts. I now proceed to give an account of such investiga- tions relating to this subject as have engaged my attention during a long period of years. It may be needful to premise certain facts which are, I believe, universally ad- mitted as indisputable ; namely, that the atmosphere consists principally of two elastic fluids, azote and oxygen, either mixed by some mechanical law, or otherwise com- bined by a chemical principle in proportion nearly as four parts of the former to one of the latter in volume ; that the two elastic fluids may be obtained separately in a state of purity ; that when thus obtained they may be mixed in all possible propor- tions; and that the aggregate volumes in such cases are just equal to the sum of the two volumes of the ingredients : also, that any body which has a chemical affinity for either of them so as to combine with it in a separate state, will also combine with it in the mixed state. It is also pretty generally admitted that oxygen and azote are capable of chemical combinations in five or more definite proportions, namely, 2 vol. of azote with 1 vol. of oxygen — forming 2 vol. of nitrous oxide. 1 vol. of azote with 1 vol. of oxygen — forming 2 vol. of nitrous gas. 1 vol. of azote with 1^ vol. of oxygen — forming 1^ vol. of hyponitrous acid. 1 vol. of azote with 2 vol. of oxygen — forming 2 vol. of nitrous acid vapour. 1 vol. of azote with 2^ vol. of oxygen — forming 2|- vol. of nitric acid. There does not appear to be a doubt of the reality of five combinations, but all chemists are not agreed as to the proportions of the volumes being precisely as above specified, chiefly because no general law has been found to obtain in such gaseous compounds. These compounds are never formed nor decomposed without manifest chemical agency ; they all contain oxygen, but no portion of it can be abstracted from any one of them without some chemical operation ; whereas nitrous gas will immediately seize the oxygen from any of the aforementioned mixtures, the same as if it was alone, 2 z MDCCCXXXVII. 348 DR. DALTON ON THE CONSTITUTION OF THE ATMOSPHERE. whatever may be the proportions. Atmospheric air itself, or any artificial mixture of the two gases in the same proportion as common air, is equally affected by nitrous gas and by every other agent. Waving at present any consideration as to the nature and properties of the above chemical compounds, 1 shall now proceed to state the means by which the propor- tions of oxygen and azote in mixtures of these two gases may best be determined. Having been engaged in this investigation occasionally for more than forty years, I may be entitled to give my opinion on this important subject in practical chemistry. Various methods of analysing common air have been discovered in the last fifty years. I have principally directed my attention to three, namely, (1.) by the use of Volta’s eudiometer and hydrogen, or (2.) by nitrous gas, or (3.) by quadrisulphuret of lime, to abstract the oxygen from the azote. First Method , by Volta’s Eudiometer . Mr. Cavendish was one of the first to investigate the changes produced by firing mixtures of hydrogen and common airs in various proportions. (Vid. Philos. Trans., 1/84.) The following Table will exhibit a lasting monument of his skill in effecting- such an investigation. Many have attempted since to improve the methods of ana- lysis, and have brought out results widely differing from those to be derived from his table ; but it is now universally allowed that his results are nearer approximations to the truth than most of those we have seen since. His method was to take 100 measures of common air and mix them with various proportions of hydrogen, beginning with upwards of 100, and gradually descending till about 20 ; then, firing each mixture by an electric spark, he marked the diminu- tion of the mixture each time as under. The following results are extracted from Mr. Cavendish’s Table, except the last column, “Amendment,” which I have attached, for reasons assigned below. Exp. Common Inflammable Diminution Amendment. Air. Air. on firing. ]. . . 100 measures mixed with 1 24-* 1 .... gave . . . 68‘6 ..... 66‘3 2. . . 100 105-5 .... . . . 64-2 65‘8 3. . . 100 70-6 .... . . . 64-7 ..... 64-9 4. . . 100 42-3 .... . . . 61-2 ..... 60‘6 5. . . 100 33-1 .... . . . 47‘6 ..... 47-4 6. . . 100 20-6 .... . . . 29-4 ..... 29'5 In the first three experiments no oxygen was found in the residuary gas ; in the fourth a trace of oxygen was found ; and in the fifth and sixth, considerable quanti- ties of oxygen were found in the residues. It is obvious that Mr. Cavendish began intentionally with an overdose of hydrogen, probably expecting the diminution to be a constant quantity till the hydrogen became deficient, and then of course the diminution must be lessened ; this was not the case DR. DALTON ON THE CONSTITUTION OF THE ATMOSPHERE. 349 exactly; but the reason is easily discovered, and it proves the accuracy of the obser- vations. Hydrogen gas is rarely obtained quite pure : it frequently holds two or three per cent, of common air, detached from the water through which it bubbles and by other means; this air increases as more water enters the hydrogen bottle, till sometimes it amounts to ten per cent, at the last, as every one knows who has had a due share of experience. Now as Mr. Cavendish does not mention the purity of his hydrogen, we must try it by the means now generally known, as the reported results will guide us in the investigation. On looking at the column headed “ diminution on firing” it is easy to see there is a discrepancy in the first three experiments in that column ; if the hydrogen used contained any oxygen the diminution on firing ought to have continually decreased, whereas if was greater in the third than in the second experiment. This it must be allowed is a proof of inaccuracy in one or both of the experiments ; but it is no greater error than usually occurs if we trust to a single experiment with any gaseous mixture. The average of two or three experiments on mixtures of the same propor- tions should be taken. The fourth experiment clearly shows that the hydrogen con- tained oxygen as well as azote; for a diminution of 6T2 would denote the union of 204 oxygen with 40'8 hydrogen ; hence there must have been T5 common air in the hydrogen. I have formed the column “ amendment” by assuming the hydrogen in all the experiments to contain 4\ per cent, common air. If we combine the results of the third and fourth experiments, either by assuming Mr. Cavendish’s diminution or that of the amendment, we shall obtain a very good approximation to the quantity of oxygen in atmospheric air, the former experiment giving too great diminution by reason of the excess of hydrogen and that containing some oxygen, and the latter giving too little diminution for want of the requisite quantity of hydrogen ; the former will give 20'98 per cent, oxygen, and the latter 20’92 per cent, oxygen in atmospheric air. If any doubt should remain as to Mr. Cavendish’s hydrogen containing oxygen, it is removed by the consideration that his first experiment would indicate 22‘9 oxygen per cent, in air, which cannot be allowed ; and his last experiment that 8-8 oxygen must have combined with 20’6 hydrogen instead of 17'6, which is equally inadmissible. Since the period 1/84 it has been found by various chemists that in mixtures of oxygen and hydrogen, as well as in other similar ones, the electric spark does not always cause an explosion, and when it does a complete combination does not always take place, but that in the residue sometimes portions of both the ingredients may be found. The limitations and restrictions are now pretty generally known ; and with regard to the mixtures of common air and hydrogen, I published a letter in the 10th volume of the Annals of Philosophy, (New Series) page 304, in which I showed the limitations found by my own experience to be as under : Common air and hydrogen in which the oxygen is only -Artlb or fi’om six to seven per cent, of the whole mixture, do not explode. 2 z 2 350 DR. DALTON ON THE CONSTITUTION OF THE ATMOSPHERE. Common air and hydrogen in which the oxygen is only -JTth, or seven per cent., ex- plode imperfectly, leaving both oxygen and hydrogen. Common air and hydrogen in which the oxygen is from ^th to 646th, or from eight to fourteen or fifteen per cent., fire leaving hydrogen and azote only. Common air and hydrogen in which the hydrogen is d^th to yth, or from fourteen to thirty per cent., fire and leave oxygen and azote only. Common air and hydrogen in which the hydrogen is Ath to -rh-th, or from eight to twelve per cent., fire imperfectly, and leave oxygen, hydrogen, and azote. Common air and hydrogen in which the hydrogen is -yVth or less than seven per cent., do not explode. It should be observed that when one of the gases is so far deficient as not to allow of an explosion by a single spark, the effect may be obtained by a current of sparks for a longer or shorter period, accompanied by the requisite diminution of volume. In such instances where the effect is produced only by a current of sparks it may be proper here to suggest the reason. When mixtures explode perfectly but feebly, we see the flame, lighted by the spark, to run down the eudiometer till it reaches the water ; when they explode still more feebly, the flame runs perhaps half way down the tube and is extinguished before it reaches the water. There scarcely can be a doubt that the extinction must be occasioned by the cooling effect of the eudiometer and of the intermixture of the mass of air which has to be heated by the feeble flame. Another spark in its passage will re-alight the flame, to suffer a quicker extinction, and so on till at length the combustion is complete. This reason will also explain the excessively slow combustion of azote by the electric spark, as ascertained by Mr. Cavendish, and as I have found by repeated experience. Query, might not this experiment succeed better by heating the eudiometer ? From what we have stated it must be obvious that in order to secure the complete abstraction of either oxygen or hydrogen from mixtures by Volta’s eudiometer, we should avoid too near an approach to the limitations we have pointed out ; or if that cannot be, we should carefully examine the residue for both gases. The best test for very small portions of oxygen is undoubtedly nitrous gas ; for somewhat larger por- tions of oxygen or hydrogen, additions of those gases might be made so as to bring the mixtures into proportions capable of being exploded. Second Method, by Nitrous Gas. The nitrous gas eudiometer is of singular utility on many occasions. No other can exceed it in accuracy when mixtures contain very little, as one or two per cent, of oxygen ; or on the other hand when nearly the whole of the gas is oxygen. But when the mixture of gases contains from twenty to eighty per cent, of oxygen, as in the case of common air, it is not the best when great exactness is required. The reason is well known ; when oxygen and nitrous gas combine, the combination is not like that of oxygen and hydrogen, in uniform proportion. We may take one third of DR. DALTON ON THE CONSTITUTION OF THE ATMOSPHERE. 351 the diminution for oxygen, when mixed over water ; but this can be considered only as a first approximation. One hundred parts of oxygen may combine with 130 or 360 parts, or any intermediate quantity of nitrous gas, according to circumstances. When only 1 or 2 percent, of oxygen are expected I put in 5 or 10 per cent, of nitrous gas, and take one third of the diminution for oxygen. When the oxygen (freed from carbonic acid) is judged to be 90 or more per cent, pure, I put 100 parts of nitrous gas of known purity (say 98 + ) to 100 of the oxygen, and mark the diminution; I next put in 40 nitrous and mark the diminution, and so on, till there is manifestly a slight portion of nitrous left ; then this is to be removed by a small portion of oxygen ; finally, knowing the quantity of azote which was in the nitrous gas, the rest must have been introduced by the oxygen. In this way I find a perfect agreement, whether the nitrous test or the hydrogen is used ; but with common air the residue is so enlarged with azote as to render the measuring of it not so accurate. Third Method, hy Qitadr [sulphur et of Lime. Quadrisulphuret of lime is an excellent test for oxygen, and may be applied to common air or to other mixtures of which oxygen is a part, up to the purest oxygen. As this and other similar compounds seem to me destined to act an important part in chemical operations, it may not be improper here to give some account of their origin and their constitution, as far as actual experiments have demonstrated. The alkalies and the alkaline earths that are soluble in water have been long known to combine with sulphur, both in the dry and humid way. In the last century they went by the name of hepar sulphuris, or liver of sulphur, from their colour. Scheele was the first to use the quadrisulphuret of lime to abstract oxygen from atmospheric air. Lavoisier also made use of the same article ; but it was to De Marti of Spain we owe the most successful attempt with the quadrisulphuret of lime to abstract the oxygen from atmospheric air. His memoir, printed in 1795, and re- printed in the Journal de Physique, vol. lii., 1801, may still be read with interest. All the hepars, when dissolved in water, have usually gone by the harsh name of hydro- curetted sulphurets in our English works of chemistry since the commencement of the present century. In 1798 Berthollet published an essay on the nature and combinations of sul- phuretted hydrogen, with reference to the part it acts in the sulphurets. Proust afterwards controverted some of Berthollets opinions in the 59th volume of the Journal de Physique, 1804. Gay-Lussac, in the 78th volume of the Annales de Chimie, 1811, gives some important results on the mutual action of metallic oxides and alkaline hydrosulphurets ; he finds amongst other results that no sulphates are formed, that water is formed, that sulphites or sulphuretted sulphites, and often me- tallic sulphurets are formed ; and that consequently it is not possible to obtain the simple metallic bases of hydrosulphurets by means of hydrosulphurets of their oxides; 352 DR. DALTON ON THE CONSTITUTION OF THE ATMOSPHERE. and that when a sulphuret is dissolved in water, no sulphate is ever formed, as is commonly imagined, but sulphites and sulphuretted sulphites. Some proofs are after- wards given*. Vauquelin, in the 6th volume of the Annales de Chimie et de Phy- sique, 1817, presents us with a laboured series of experiments on the alkaline sul- phurets, the chief object of which is to ascertain the state of the alkali in the sulphuret, whether it is that of a metal or of an oxide. After many experiments on the sul- phurets of potash, soda, and lime in the dry way, and one on sulphuret of lime in the humid way, the author sums up, and notwithstanding his leaning to the opinion that the alkalies exist in sulphurets in the state of metals , he is obliged at last to ac- knowledge “ that it is probable, but not yet demonstrated , that in all the sulphurets formed by means of the alkaline oxides by a red heat, these last lose their oxygen, and are united to sulphur in the metallic state, as is the case with the other metals.” Gay-Lussac, in the sequel of the same volume, page 322, in a memoir, animadverts on the before-cited paragraph ; and allowing that sulphuric acid is formed when a sulphuret of potash made by a red heat is dissolved in water, he contends, according to a suggestion of Berthollet, that the acid is formed in the instant of solution from the reciprocal action of the sulphuret and the water, rather than from the oxygen of the potash and sulphur. This opinion is countenanced by several combinations of a similar nature, which he has adduced, and which are worth the attention of chemists. Without adverting at present to my own experiments, I may observe that Sir John Herschel, in an essay in the first volume of the Edinburgh Philosophical Journal, 1819, was the first writer who published an atomic view of the class of salts called sulphuretted sulphites, or hyposulphites, that accorded with what 1 had long enter- tained and demonstrated by reiterated and decisive experiments •f-. In the above- mentioned essay he showed clearly that the hyposulphurous acid is composed of two atoms of sulphur and two of oxygen, which united to one atom of base, as potash or lime, compose an atom of a hyposulphite. The formation of those of lime, potash, soda, barytes, and some metallic oxides is more particularly explained. A saturated solution of hyposulphite of lime at 50° he found to be L30 specific gravity^. In the 14th volume of the Annales de Chimie et de Physique, Gay-Lussac has given the principal results of Herschel’ s essays on the hyposulphurous acid with some judi- cious remarks, but he leaves the subject as one requiring further investigation. In 1822 Berzelius published a memoir on the alkaline sulphurets. The results of his experiments seemed to him confirmatory of the previous notion of Vauquelin. Those experiments were on the sulphurets of potash and lime made in the dry way ; he made only one on lime, which agreed very well with the theory ; but this very * See also vol. lxxxv. p. 199. t See New System of Chemical Philosophy, vol. ii. Preface, and p. 105. X Dr. Thomson, in a paper on the compounds of chromium in the Transactions of the Royal Society for 1826, disputes the accuracy of this constitution of hyposulphurous acid. I have never had any doubt concerning it since 1815. DR. DALTON ON THE CONSTITUTION OF THE ATMOSPHERE. 353 delicate experiment was not enough to establish so important a law of combination, and I do not find that any one besides has obtained the same result*. Though I am not prepared to deny that sulphurets of potassium and calcium can be obtained by the process of Berzelius, I am quite satisfied that sulphurets of potash and lime, &c. may be easily procured in the dry way: of that of lime I have had numberless instances. As the compounds of sulphur and the alkaline earths have been very little subjected to investigation by chemists in general, we find great vacancy in the accounts given of them by the modern compilers of chemical books. For this reason I shall introduce here a few of the results I have obtained in a long series of experiments on this branch of chemical inquiry, Sulphuret of Lime, in the dry way. In 1806 I formed, for the first time, the protosulphuret of lime by heating 50 grains of fallen lime with 50 sulphur in a covered crucible not quite air-tight, so that the escape and combustion of the excess of sulphur might be allowed ; when raised to a red heat an addition was made to the weight of the lime ; by repeating the dose of the sulphur and heating, a further addition was made to the weight ; but repeating the operation a third time seldom made any further addition. The weight of the compound was 65 grains ; it was a white powder with a tinge of yellow, not caustic, but bitter to the taste. In 1809 I examined this powder more minutely, and found it was best made by mixing equal weights of pure hydrate of lime and flowers of sulphur, putting the mixture into a covered crucible and heating it slowly to red ; when the escape of the sulphur fumes ceases, cool the contents, and again mix them with the same weight of sulphur as in the first operation, and again heat it as above ; at last it will be found that 32 parts of hydrate of lime — 24 lime have combined with 14 of sulphur, or one atom to one-f'. In the work referred to I have stated that pounded lime and sulphur scarcely form any union by this process, and carbonate of lime and sulphur still less. An ingenious pupil of mine, Mr. William Barnett Watson of Bolton, has succeeded in uniting lime and sulphur by heat; instead of taking pounded lime, which has a harsh gritty feel, he takes hydrate of lime, and expels the water by a red heat con- tinued till 32 parts of hydrate are reduced to 24 ; this is a fine soft powder ; when 24 parts of this pure and finely divided lime freed from water are well mixed with 24 parts of sulphur and heated red in a covered crucible, a partial combination takes place, and an increase of weight to the lime ; this operation is to be repeated till the additional weight becomes 14 grains, after which no further addition can be effected. Mr. Watson found it require several repetitions. I have since found it may be effected by two or three only. This sulphuret is not used in eudiometry. * Annals of Philosophy, 1822. f See New System of Chemical Philosophy, vol. ii. pages 99 and 102. 354 DR. DALTON ON THE CONSTITUTION OF THE ATMOSPHERE. Quadrisulphuret of Lime, in the humid way. When sulphur and hydrate of lime in almost any proportions are boiled together in water, quadrisulphuret of lime is formed and dissolved in the water ; the solution is of a deep yellow colour, and has a very bitter taste. I have not seen in any author the proportion that ought to be used, nor the quantity and specific gravity of the liquid solutions. These are subjects which have engaged my attention. If lime is in excess, the liquid consists of lime water holding in solution quadrisulphuret of lime. If sulphur is in excess, the liquid consists of water holding in solution quadrisulphuret of lime. I have long known that the economical proportions to be used are 32 parts of dry hydrate of lime by weight with 56 of sulphur, that is, one atom of lime with four atoms of sulphur. If more lime than that above be used, it will be found pre- valent in the residue ; if more sulphur, then the redundant sulphur will be found in the residue. A few ounces of the mixed ingredients may be gently boiled in an iron pan for an hour or more, stirring the liquor occasionally, and covering the pan with a lid to prevent the too free admission of atmospheric air. Or, in order to prevent the action of oxygen on the liquid, a flask may be substituted for the pan ; the ma- terials may be put into the flask nearly filled with water, and the flask loosely corked may be immersed in a pan of boiling water so as to be almost covered by the water. The liquor to be preserved should be kept in green glass bottles nearly full, and having ground stoppers. After the boiled liquor has cooled and the sediment subsided, the clear liquor may be decanted ; if it be strong or deep coloured the sediment may be washed with a little water, and another quantity of the liquor obtained of inferior strength. The sediment may be dried if necessary, and subjected to analysis, as I have mostly done. The quantity and specific gravity of the clear liquors should then be ascertained. The first quadrisulphuret of lime I made was in 1804 ; it was very weak, since it only absorbed one fourth of its bulk of oxygen gas ; the next that was made took its bulk of oxygen. The next, made in 1806, took times its bulk of oxygen. In these no account was taken of quantities or residues of lime and sulphur. After this I saw the necessity of investigating, (1.) the quantities of lime and sulphur mixed ; (2.) the quantity and specific gravity of the liquid obtained ; and (3.) the quantity and pro- portion of the materials left in the residue, in order that the rationale of the changes effected might be explained. From 1806 to the present time (1837) I have made no quadrisulphuret of lime without attending to all those particulars. In this period I have made it 23 times, six of which were in flasks, and the rest in iron pans covered as mentioned above ; the difference of the two methods I found to be very little ; it consisted chiefly in traces of sulphuret of iron being found in the residues when pans were used. A few trials of the various liquids obtained soon furnished me with a formula for ascertaining the quantities of sulphur and lime in a liquid of given specific gravity ; DR. DALTON ON THE CONSTITUTION OF THE ATMOSPHERE. 355 namely, multiply the three leading decimals in the specific gravity of the liquid by 13, and the product will give the aggregate weight in grains of sulphur and lime in 1000 water grain measures of the liquid ; of this aggregate -j^-th will be sulphur, and T43th lime. With regard to the residue after boiling and its analysis, it is obvious the residue must consist chiefly of sulphur and lime, which for want of due continuance of the ebullition have escaped combination ; and there may be some impurities in the sulphur, or the hydrate of lime may not be free from carbonate, &c. ; but when the residue is comparatively small no material disturbance of proportions in the qnadri- sulphuret can take place. If the residue be chiefly sulphur, its quantity may be ap- proximated by ignition ; but if lime is in excess, it may be estimated by the quantity of muriatic acid required to saturate it. The following Table exhibits a selection of the principal varieties in the proportions of ingredients and products obtained so as to illustrate the foregoing statements. Table of Proportions in Quadrisulphuret of Lime. Quantities of hydrate of lime and sulphur mixed. Proportions of lime and sulphur. Quantity of liquor obtained in water grain measures, and quantities of lime and sulphur in it. Measures of oxygen required to saturate 100 liquid. Quantity of residue when dried. 1 Hydrate. Sulphur. 120 = 90 lime + 210 Lime. 4 : Sulph. 3100 of 1 '056 containing 70 lime + 156 sulph. 900 56 = 16 lime + 40 sulph. 2 50 = 2,11 lime + 50* * * § 4 : 2200 of 1-0240 containing 21 lime + 47 sulph. 400 20 = 12 lime + 4 sulph. + loss. 3 150 = 112f lime + 200 4 : 7 + 1450 of 1-146 containing 85 lime + 190 sulph. 2350 f20 = 7 lime + 13 sulph. 4 96 = 72 lime + 168 sulph. f 4 : H 2800 of 1-056 containing 63 lime + 141 sulph. 900 § 34 = 9 lime + 25 sulph. 5 35 = 26 lime + 140 sulph. 4 : 21-6 1600 of 1-037 containing 23-7 lime + 53-3 sulph. 600 § 83 all sulph. On the Quantity of Oxygen in the Atmosphere. Since the commencement of the present century it has been ascertained beyond dispute that the chief constituents of the atmosphere, oxygen gas and azotic gas, are in the same proportion in all countries and at all times, except when influenced by local circumstances ; namely, 21 per cent, of volume of oxygen, and 79 per cent, of azote, neglecting fractions : other elements are found in the atmosphere, but they are comparatively insignificant in quantity, namely aqueous vapour, carbonic acid, &c. The experiments have generally been made on air collected at the surface of the earth ; and it may be remembered that I have endeavoured to prove in various essays that the diffusion of gases one amongst another as well as in vacuo, is owing to the repulsive powers peculiar to the particles of each particular gas, otherwise we * Boiled in a flask loosely corked. t Lost some of the ingredients by boiling over ; hence a deficiency. 1 Boiled in a flask with great care. § The oxygen was determined by especial care in these two cases. MDCCCXXXVII. 3 A 356 DR. DALTON ON THE CONSTITUTION OF THE ATMOSPHERE. should never have the feeble efforts of carbonic acid and aqueous vapour diffusing1 those elements against the immense pressure of the atmosphere. The principle I contend for has, I believe, obtained general assent ; but I apprehend few have been aware of the consequences. If we suppose a carbonic acid atmosphere of 15 inches of mercury pressure and a hydrogen atmosphere of the same pressure, together con- stituting a mixture of the two amounting to 30 inches of pressure, were to surround the earth, I think no one would hazard a conjecture that these two would be found in equal proportions at every elevation in the atmosphere ; yet a similar supposition seems prevalent with regard to our present atmosphere of oxygen and azote. It has been an object of investigation with me for many years to find how the fact stands in this respect ; that is, whether the oxygen is more abundant relatively in the lower strata of the atmosphere than in the higher, as it ought to be in a stagnant column ; or whether the constant agitation of the atmosphere and the predominant mechanical power of the azotic part of it do not prevent that equilibrium which a stagnant mixture of aerial fluids of different specific gravities would effect. From the experi- ments about to be related, I have reason to believe that the higher regions of the atmosphere are somewhat less abundant in the proportion of oxygen than the lower, though the reverse might be expected from the enormous consumption of oxygen by daily processes on the surface of the earth, when we know of no proportionate con- sumption of azote. It appears, however, that the disproportion of the two elements at different elevations is by no means so great as theory requires ; and therefore we must conclude the unceasing agitation of the atmosphere by currents and counter- currents is sufficient to maintain an almost uniform mixture at the different elevations to which we have access. The subject is one involving an important principle. I have kept it continually in view for the last forty years, and have made innumerable experiments with a view to its elucidation. As the value of such experiments depends much upon a thorough acquaintance with the nature of the operations and the several sources of error to which they are liable, it may be needful to point out certain particulars, which, as long experience has taught me, require attention in order to secure a due approxima- tion to accuracy. I allude more particularly to the use of Volta’s eudiometer as applied to determine the proportions and quantities of oxygen and hydrogen gases. 1. Hydrogen gas procured over water is sure to contain some common air, whether the water has been previously boiled or not ; it arises out of the water and may amount to 1 or 2 per cent. ; the same observation applies to oxygen gas ; the pro- portion of oxygen and azote is usually that in common air nearly. When a phial of hydrogen gas, by long keeping or by accident, has acquired a portion of common air, and then stood some weeks after, the oxygen seems to diminish, either by slow combustion or by absorption in the water, and so leaves the azote and oxygen in another proportion to that of common air. Before using such hydrogen the oxygen in it should be tested by nitrous gas, and the percentage of hydrogen by oxygen gas. DR. DALTON ON THE CONSTITUTION OF THE ATMOSPHERE. 357 It is best not to rely too much upon hydrogen taken from a bottle half filled with water. 2. Oxygen gas, and others, will show carbonic acid by sending them up through a narrow eudiometer tube filled with lime-wTater, provided the acid gas amounts to \ per cent, of the original ; but it does not show any carbonic acid in this way in atmospheric air, though the acid is always present to the amount perhaps of 10j0th part. The proportion of pure oxygen in any sample containing from 90 to 100 per cent, of that gas, may be found either by hydrogen gas or nitrous gas ; and if great accuracy is required, I recommend testing it both ways, as has already been men- tioned under the head nitrous gas. 3. The gradual deterioration of oxygen, hydrogen, nitrous gas, common air, &c., when by use the phial becames or f filled with trough water, is a circumstance by no means to be overlooked. The entrance of water that has been sometime stagnant in the cistern, though preserved carefully from any material impurities, always affects the remaining air, though the phial be w’ell corked and immersed in a cup of water. The cause is obvious to those acquainted with the laws that regulate the absorption of gases by water. The common air in the water (the quantity of which varies much as to the oxygen part) is continually either making its escape into the incumbent air of the phial, or this last air is entering the water, so that the de- gree of purity is continually changing in a small degree. This renders it necessary to test the actual state of this gas after it has been some time in the phial, before we recommence the use of it. A phial of air may be pure at first, and only 90 per cent, at its conclusion. I have known samples of common air kept in bottles at first con- taining 21 per cent, of oxygen, and after some months a small residue was found to contain only 19 per cent. 4. It may not be improper here to relate some unpublished results which I formerly obtained when experimenting on subjects here discussed. In my memoranda for 1816, I find that I took water well boiled (supposed i of an hour or more) and then poured it gently into a Florence flask, filling it up into the narrowest part of the neck, and left it so, exposed to the atmosphere for three days without any agitation. At the end of this, 2700 grains of water imbibed 49 grain measures of atmospheric air by agitation, which is about -f- of a full share ; hence -j- of a full share must have been, both the air that was left in after boiling, and that acquired from the atmo- sphere in three days by absorption from the small exposed surface. Water boiled in a kettle for three or four minutes, then suddenly cooled and trans- ferred without agitation into a bottle containing 2700 grains, and then agitated with atmospheric air, imbibed 32 measures, which are about half a charge ; whence it may be inferred that water boiled for three or four minutes loses about half of its air. I boiled a kettle full of water for a quarter of an hour ; let it stand a day or two to cool, then transferred it carefully by a siphon into a cylindric jar of 8 inches dia- meter and 10 inches deep; afterwards drew off daily by a siphon 2700 grain mea- 3 a 2 358 DU. DALTON ON THE CONSTITUTION OF THE ATMOSPHERE. sures from the middle or near the bottom of the jar, and charged it with air to the full by agitation. The bottle of water imbibed The water taken near the surface. These portions taken up consisted nearly one half of oxygen. es. From these experiments it would appear that by boiling water briskly for three or four minutes, about half of the atmospheric air previously in the water escapes along with the steam. But it requires much longer boiling and keeping the atmospheric air as much as possible from the surface of the water to get the rest of the air ex- pelled. It is never all expelled by boiling, except in the construction of a good water hammer. Any one air not chemically combined with water is easily and effectually expelled from it by repeatedly agitating the water with another kind of air. It also appears that water deprived of its atmospheric air, if kept at rest, acquires the air again slowly, and more so if the surface exposed is small. But if violent agi- tation of the water, so as to mix the atmospheric air and it intimately together, be used, the full impregnation is effected in one or two minutes, as I have elsewhere shown. Trough waters being mentioned above (3.) it may be well to explain some of the circumstances affecting it. The waters I use for the chemical trough is rain-water ; it is preferable to pump water by its freedom from carbonic acid and earthy salts ; it is slightly coloured at first when drawn from the cistern, but it soon becomes clarified by standing: my trough contains about nine gallons when in work. I take great care to put nothing in it which can materially affect its purity ; small portions of lime water and of some iron and other salts are the chief impurities which are ad- mitted ; no sulphurets or hydrosulphurets are allowed to enter, and very little of either acids or alkalies. I examine the state of the water occasionally ; lately, after it had been more than half a year in the trough, though not very frequently used, I had the curiosity to examine its state before the trough was emptied. The water was neutral by the colour test ; it contained about 50 grains of saline matter in the gal- lon ; it was transparent, but slightly milky ; prussiate of potash gave sensible blue ; oxalate of ammonia, muriate of barytes, and carbonate of soda produced a white pre- cipitate. The taste was like that of earthy pump water. It had its full share of The first day . . . 16 measures. The second day . 15 measures. The third day . . 12 measures. The fourth day . . 10 measures. The fifth day . . . 10 measures. The sixth day . . 9 measures. The seventh day. . 4 measures. The eighth day . . 7 measures.^ The ninth day . . 9 measures. The tenth day . . 7 measures.^ The fifteenth day . 2 or 3 measu DR. DALTON ON THE CONSTITUTION OF THE ATMOSPHERE. 359 azotic gas, but rather less than half of its share of oxygen gas ; that is, it had about 4 or 5 cubic inches of azote in the gallon, and only 1 cubic inch of oxygen. In the following train of experiments on the oxygen in the atmosphere I have mostly used from 50 to 70 measures of hydrogen for 100 air, unless otherwise men- tioned. Possibly this may not be thought the best proportion for securing the com- plete abstraction of the oxygen. The limits are, 100 air with 42 of hydrogen for the minimum, and 100 air with 1/0 hydrogen for the maximum. In the former case the hydrogen is barely sufficient for the oxygen ; in the latter case the oxygen is barely enough to admit of a complete combustion, being only -^-th of the mixture. Perhaps the best proportion would be 100 air to 100 hydrogen to ensure complete combustion, because it is about the mean of the two extremes ; but it must be considered that if the hydrogen should contain even a very small portion of oxygen, the whole of it in 100 measures would be included in the atmospheric oxygen, so that in practice it would probably be safest to use a mean between 40 and 100 of hydrogen. I have mostly endeavoured to keep between 50 and 70 of hydrogen for 100 air. Experiments on the Quantity of Oxygen in Atmospheric Air. Air from the Summit of Helvellyn*, July 14, 1824. A phial, containing about half a pint, was filled with water at a clear rivulet on the ascent ; this was emptied at the summit and well corked ; the cork was drawn at the foot of the mountain in a trough of clear running water, when a quantity of water was found to enter corresponding to the increased pressure of the atmosphere. The phial was then corked and inverted in a cup of water, and the air analysed a week afterwards. Average of four experiments on this air with hydrogen, about l 2070 oxygen 50 to 100 air, gave J per cent. Average of four experiments of the common air taken in Man--\ Chester at the time of the analysis, and with same phial of ^ oxy§en hydrogen and same proportion, gave J Pei cent- Average of seven experiments on Helvellyn air made a day i 20'58 oxygen afterwards, gave J per cent. Average of seven experiments on air from an open place in the "i 21*1 oxygen town next day with same hydrogen, gave J per cent. Average of eight experiments on the country air three miles ^ from Manchester, July 29, with same phial of hydrogen, oxy&en which now manifested a very slight trace of oxygen, gave J ^ei cen^' 1824, November 23. — Barometer 28 inches, very low. Apprehending that this * This mountain, situate at the head of Ullswater, separates Cumberland from Westmoreland ; its height above the sea, which lies to the S.W., and from which it is distant about 20 miles, is upwards of 3000 feet ; it is surrounded by other mountains, mostly of less elevation. 360 DR. DALTON ON THE CONSTITUTION OF THE ATMOSPHERE. circumstance, attended by rain and a high wind S.E., might have some influence on the proportions of the atmosphere, I made the following experiments. Average of six experiments gave 20’75 oxygen per cent. When the remainder of this air had been kept five months in the bottle, it then yielded on an average of three experiments 20 67 oxygen per cent. 1825, January 8. — Barometer 30 94, extremely high, after a week of calm weather. Filled a bottle with air from the town. Average of four experiments with two parts air and one hydrogen gave 21-12 oxygen per cent. The remainder of this air, kept till August same year, gave 21*1 oxygen per cent. June 8. — Average of four experiments from air in the town gave 20-97 oxygen per cent. ; barometer 29-90. June 10. — Air from a field near the town, barometer being 30’30, thermometer 70°, wind S.W. ; sunny and sultry. Two parts of the air with one of pure hydrogen being mixed, the average of six experiments gave 20-58 oxygen per cent. June 14. — Mixed some pure azotic gas with oxygen gas, which was marked 90 per cent, pure, in such proportions as to make a mixture of 21 per cent, oxygen. On trial with hydrogen the mixture gave, first experiment 21 -f- oxygen percent.; the second experiment 20*9 oxygen per cent. November 3. — Air in the town, barometer 28‘76, thermometer 46°, rainy, with S.W. wind. Average of ten experiments gave 20-6 oxygen per cent. Air from the Summit of Snowdon, 3570 feet above the sea, taken by John Black- wall, Esq., May 14, 1826, at 7 p.m. ; wind N.E. light, barometer 26-20, thermo- meter 42°. May 28. — Average of ten experiments gave 20'65 per cent, oxygen. Country air three miles from Manchester, analysed the same day, average of six experiments gave 20’8 per cent, oxygen. Again, Snowdon air in six experiments gave 20"66 oxygen per cent. ; but the bottle being now half full of water, I did not examine the rest. Another bottle of air was taken at the summit on another occasion, May 18, by the same gentleman ; wind S.W., light. May 25. — Analysed ; average of six experiments gave 20-59 oxygen per cent. Country air near Manchester at same time gave average 20‘7 per cent. A second bottle of air from Snowdon, taken at the same time. May 18, gave on an average of four experiments 20*9 oxygen per cent. Air from the town at the same time, on an average of five experiments, gave 2T04 oxygen per cent. 1826, July, Air from the Summit of Helvellyn. Average of ten experiments gave 20-63 oxygen per cent. Average of the town air found at same time was 20'73 oxygen per cent. DR. DALTON ON THE CONSTITUTION OF THE ATMOSPHERE. 361 Air taken in an Aerial Voyage over Cheshire. Mr. Grafton was so good as to procure me a bottle of air taken in an aerial voyage over Cheshire with Mr. Green, June 26, 1827 ; height 9600 feet above the sea*. The air was transferred into two phials. First Phial. June 2/. — Average of seven experiments of balloon air gave Average of seven experiments on town air gave . July 2. — Average of eight experiments of balloon air gave Average of eight experiments on town air gave . 20*7 oxygen per cent. 20-83 20*2f 20-8 The second phial of balloon air was carefully preserved, the phial being filled and having a ground stopper. It was analysed. 1 828, May 28. — Average of three experiments balloon air gave Average of three experiments town air gave . Aug. 5. — Average of thirteen experiments, being the whole of the balloon air, gave .... Average of thirteen experiments on town air gave 20*92 20*70 oxygen per cent. 20*80 20*52 On the last-mentioned day I received a bottle of air from the summit of Snowdon through the care and attention of my friend and pupil Mr. John Hall. It was corked and well sealed with wax ; when opened under water a due portion of that fluid entered. The average of the first two experiments gave 20*44 oxygen per cent. The rest of the air after these two experiments was divided into two portions, and entered into two phials for examination. These were analysed a week or two after- wards. Average of five experiments with first phial gave 20*25 oxygen per cent. Average of four experiments, which emptied the first phial, gave 19*98 oxygen per cent. Average of seven experiments of second phial gave 20*3 oxygen per cent. ; and a considerable portion was left. Average of the town air was during these experiments nearly 21 oxygen per cent. I am not aware of any cause why this air was so much inferior in oxygen to that on former occasions. * Height found as under : Capacity of bottle 10*47 ounces. On drawing the cork under water there entered . 2*77 ounces. Left . . . 7*7 ounces of air. Also height of barometer and thermometer below given. f The whole air in the first phial was spent in these fifteen experiments. The deterioration of the air in the first phial, by being kept half full of trough water for five days, is remarkable. 362 DR. DALTON ON THE CONSTITUTION OF THE ATMOSPHERE. 1831, July 4. — Helvellyn air brought down from the summit by me ; wind S.W., with rain and fog. 1. July 21. — Mixed two ounce measures of this air with one of hydrogen, so as to make six separate and successive explosions ; the hydrogen had iVths of a grain measure per cent, of oxygen, and this is allowed for in the corrected results. These results on the average gave 20-57 oxygen per cent. ; the highest was 20-68, and the lowest was 20'43. The residues of the six explosions were collected, and found to have 5 per cent, of hydrogen and 1 in 120 of oxygen. 2. Mixed equal volumes of this Helvellyn air and the same bottle of hydrogen used above, and tired the mixture in successive portions. The average of six experiments gave 20’8 per cent, of oxygen. No oxygen was found in the residue. By comparing the results of 1 and 2, it would seem that more oxygen is reduced from common air by tiring equal volumes of common air and hydrogen than by tiring one volume of common air with half a volume of hydrogen. August 23. — Mixed 100 measures of town air and 120 of new pure hydrogen; this fired gave 21*5 oxygen per cent.; there was no oxygen in the residue. This would seem to point out ^^q^th of oxygen in the hydrogen, yet nitrous gas scarcely mani- fested so much. 1832, July 26. — Mr. Green, jun., and Mr. John Taylor of the Manchester gas works, ascended in a balloon from Manchester after 6 p.m., a tine, clear, calm evening, barometer being 30 inches, thermometer 65° ; the balloon took a south direction, and landed in Cheshire about fourteen miles off. Mr. Taylor took a bottle of air when at the highest elevation, when the barometer stood at 16'8 inches, thermometer 55°; whence the altitude must have been about 15,000 feet. Capacity of the bottle = 2406 grains of water. On opening it under water in temp. 64° there entered 884 grains of water. The air was soon after its reception on the 27th transferred into two small phials for examination. The first phial was mixed with 60 per cent, of hydrogen, and fired in five portions ; it yielded 20’59 oxygen per cent. The second phial, mixed in like proportion, gave 20’65 oxygen per cent. Air from the town the next day, fired with the same phial of hydrogen as the pre- ceding, gave 20-95 on the average of five experiments. Air from Switzerland, & c. In the autumn of 1835 I was favoured with three samples of air taken in elevated situations in Switzerland by my friend W. D. Crewdson, jun. Esq., of Kendal. Each of these was taken in a two ounce phial by pouring out the contained water and DR. DALTON ON THE CONSTITUTION OF THE ATMOSPHERE. 363 corking the phial immediately, leaving only a drop or two of water within. The cork was then well closed with sealing-wax. No. 1 was taken on the Mer de Glace, Aitgust 21, estimated at the height of 6000 feet above the sea; the second on the pass of the Simplon, August 29, at the height of 6174 feet above the sea; and the third on the Wenger n Alp on the 15th September, at the height of 6230 feet. These airs were analysed in October with the following results. Mer de Glace. — Average of four first experiments 20*2 oxygen per cent. Average of four last experiments 19*4 oxygen per cent. Simplon. — Average of four first experiments 1 9*98 oxygen per cent. Average of four last experiments 19'53 oxygen per cent. Wengern Alp. — Average of four first experiments 20*45 oxygen per cent. Average of four last experiments 20*11 oxygen per cent. It may not be amiss to subjoin a few experiments on air in close chambers, where a number of people have been congregated for two hours, the air being taken at the moment of breaking up. 1802, March 6. — Got a 20-ounce phial filled at the close of a congregation of 500 people assembled for two hours with 50 candles burning ; the air completely neutralized 150 grains of lime water, but took very little more; this accords nearly with 1 per cent, of carbonic acid gas. The oxygen was not examined. 1824, November 28. — Examined the air at the close of an ordinary congregation, perhaps 200 people, retained for two hours. Average of five experiments gave the oxygen 20*42 per cent. 1826, March 16. — Examined the air from a crowded congregation after two hours’ confinement, but some doors open. Average of four experiments gave the oxygen 20*23 per cent. There was a very slight appearance of carbonic acid each time a charge was passed up through lime water, a phenomenon never observed in ordinary atmospheric air. The general conclusions, it seems to me, to be drawn from these experiments are, that the proportion of oxygen to azote in the atmosphere on the surface of the earth is not precisely the same at ail places and times ; and that in elevated regions the proportion of oxygen to azote is somewhat less than at the surface of the earth, but not nearly so much so as the theory of mixed gases would require ; and that the reason for this last must be found in the incessant agitation in the atmosphere from winds and other causes. June 6, 1837- 3 B MDCCCXXXVII. ■ • • • - . ■ ' XX. On the Hereditary Instinctive Propensities of Animals. By Thomas Andrew Knight,, Esq. F.R.S. President of the Horticultural Society , fyc. fyc. Received May 15, — Read May 25, 1837. In a communication which I had the honour many years ago to address to this So- ciety upon the Economy of Bees, I gave an opinion that families of those insects, in common with those of every species of domesticated animal, are to a greater or less extent governed by a power which I have there called “ an instinctive hereditary pro- pensity that is, by an irresistible propensity to do that which their predecessors of the same family have been taught or constrained to do, through many successive ge- nerations. In that communication I stated that a young Terrier, whose parents had been much employed in destroying Polecats, and a young Springing Spaniel, whose ancestry through many generations had been employed in finding Woodcocks, were reared together as companions, the Terrier not having been permitted to see a Polecat, or any other animal of similar character, and the Spaniel having been prevented seeing a Woodcock, or other kind of game ; and that the Terrier evinced, as soon as it per- ceived the scent of the Polecat, very violent anger ; and as soon as it saw the Polecat attacked it with the same degree of fury as its parents would have done. The young Spaniel, on the contrary, looked on with indifference ; but it pursued the first Wood- cock which it ever saw with joy and exultation, of which its companion, the Terrier, did not in any degree partake. I had at that period made a great many analogous experiments, and I have subse- quently made a considerable number, chiefly upon one variety of dog, namely, that which is generally used in search of Woodcocks, and is usually called the Springing Spaniel. These experiments were commenced nearly sixty years ago, and occupied a good deal of my attention during more than twenty years, and to a less extent nearly to the present time ; and as it does not appear to me probable that any person is now likely to investigate this subject as laboriously, or through so long a period, I have been induced to believe that the facts which I am prepared to communicate may be thought to deserve to be recorded in the Transactions of this Society. At the period in which my experiments commenced, well-bred and well-taught Springing Spaniels were abundant, and I readily obtained possession of as many as I wanted. I had at first no other object in view than that of obtaining dogs of great excellence; but within a very short time some facts came under my observation which very strongly arrested my attention. In several instances young and wholly inexperienced dogs appeared very nearly as expert in finding Woodcocks as their ex- 3 b 2 366 MR. KNIGHT ON THE HEREDITARY INSTINCTIVE perienced parents. The woods in which I was accustomed to shoot did not contain Pheasants, nor much game of any other kind, and I therefore resolved never to shoot at anything except Woodcocks, conceiving that by so doing the hereditary propen- sities above-mentioned would become more obvious and decided in the young and untaught animals ; and I had the satisfaction, in more than one instance, to see some of those find as many Woodcocks, and give tongue as correctly, as the best of my older dogs. Woodcocks are driven in frosty weather, as is well known, to seek their food in springs and rills of unfrozen water, and I found that my old dogs knew about as well as I did the degree of frost which would drive the Woodcocks to such places ; and this knowledge proved very troublesome to me, for I could not sufficiently re- strain them. I therefore left the old experienced dogs at home, and took only the wholly inexperienced young dogs; but to my astonishment, some of these, in several instances, confined themselves as closely to the unfrozen grounds as their parents would have done. When I first observed this I suspected that Woodcocks might have been upon the unfrozen ground during the preceding night, but I could not discover (as I think I should have done had this been the case) any traces of their having been there ; and as I could not do so, I was led to conclude that the young dogs were guided by feelings and propensities similar to those of their parents. The subjects of my observation in these cases were all the offspring of well-in- structed parents, of five or six years old, or more ; and 1 thought it not improbable that instinctive hereditary propensities might be stronger in these than in the offspring of very young and inexperienced parents. Experience proved this opinion to be well- founded, and led me to believe that these propensities might be made to cease to exist, and others be given ; and that the same breed of dogs which displayed so strongly an hereditary disposition to hunt after Woodcocks, might be made ultimately to display a similar propensity to hunt after Trufles ; and it may, I think, be reason- ably doubted whether any dog having the habits and propensities of the Springing Spaniel would ever have been known, if the art of shooting birds on wing had not been acquired. I possessed one young Spaniel, of which the male parent, apparently a well-bred Springing Spaniel, had been taught to do a great number of very extraordinary tricks (some of which I previously thought it impossible that a dog could be made to learn), and of which the female parent was a well-taught Springing Spaniel ; and the puppy had been taught, before it came into my possession, a part of the accomplishments of its male parent. This animal possessed a very singular degree of acuteness and cunning, and in some cases appeared to be guided by something more nearly allied to reason than I have ever witnessed in any of the inferior animals. In one instance I had walked out with my gun and a servant, without any dog, and having seen a Wood- cock, I sent for the dog above-mentioned, which the servant brought to me. A month afterwards I sent my servant for it again, under similar circumstances, when it acted PROPENSITIES OF ANIMALS. 367 as if it had inferred that the track by which the servant had come from me would lead it to me. It left my servant within twenty yards of my house, and was with me in a very few minutes, though the distance which it had to run exceeded a mile. I repeated this experiment at different times, and after considerable intervals, and uni- formly with the same results, the dog always coming to me without the servant. I could mention several other instances, nearly as singular, of the sagacity of this animal, which I imagined to have derived its extraordinary powers in some degree from the highly cultivated intellect of its male parent. I have witnessed, within the period above mentioned, of nearly sixty years, a very great change in the habits of the Woodcock. In the first part of that time, when it had recently arrived in the autumn, it was very tame ; it usually chuckled when dis- turbed, and took only a very short flight. It is now, and has been during many years, comparatively a very wild bird, which generally rises in silence, and takes a compa- ratively long flight, excited, I conceive, by increased hereditary fear of man. I procured a puppy of a breed of Setters, which had, through many generations, been employed in setting Partridges for the flight net only, and of whose exploits I had heard many very extraordinary accounts. I employed it as a pointer in shooting Partridges ; and for finding coveys of those birds in the open field, I never saw its equal, or in its manner of setting them ; but it would never set its game amongst brakes or hedge-rows. Whenever it found a bird in such a situation, it invariably sat down, in the same attitude, and alternately looked into the bush and at me, seem- ing to think that setting Partridges in such situations was not a part of its duty. It is well known that very young Pointers, of slow and indolent breeds, will point Partridges without any previous instruction or practice. I took one of those to a spot where I had just seen a covey of small Partridges alight in August, and amongst them I threw a piece of bread to induce the dog to move from my heels, which it had very little disposition to do at any time, except in search of something to eat. On getting amongst the partridges and perceiving the scent of them, its eyes became suddenly fixed, and its muscles rigid, and it stood trembling with anxiety during some minutes. I then caused the birds to take wing, at sight of which, it exhibited strong symptoms of fear, and none of pleasure. A young springing Spaniel, under the same circumstances, would have displayed much joy and exultation, and I do not doubt but that the young Pointer would have done so too, if none of its ancestry had ever been beaten for springing Partridges improperly. The most extraordinary instance of the power of instinctive hereditary propensity, which I have ever witnessed, came under my observation in the case of a young dog of a variety usually called Retrievers. The proper office of these dogs is that of finding and recovering wounded game, but they are often employed for more ex- tensive purposes, and are found to possess very great sagacity. I obtained a very young puppy* of this family, which was said to be exceedingly well bred, and had * It was only one month old when it came into the author’s possession. 368 MR. KNIGHT ON THE HEREDITARY INSTINCTIVE been brought to me from a distant county. I had walked up the side of the river which passes by my house in search of Wild Ducks, when the dog above mentioned followed me unobserved, and contrary to my wishes, for it was too young for service, not being then quite ten months old. It had not received any other instruction than that of being taught to bring any floating body off a pond, and I do not think that it had ever done this more than three or four times. It walked very quietly behind my gamekeeper upon the opposite side of the river, and it looked on with apparent in- difference whilst I killed a couple of Mallards and a Widgeon, but it leaped into the river instantly upon the gamekeeper pointing out the birds to it, and it brought them on shore, and to the feet of the gamekeeper, just as well as the best instructed old dog could have done. I subsequently shot a Snipe, which fell into the middle of a large nearly stagnant pool of water, which was partially frozen over. I called the dog from the other side of the river and caused it to see the Snipe, which could not be done without difficulty : but as soon as it saw it, it swam to it, brought it to me, laid it down at my feet, and again swam through the river to my gamekeeper. I never saw a dog of any age acquit itself so well, yet it was most certainly wholly untaught. I state the circumstances with reluctance, and not without hesitation, because I doubt whether I could myself believe them to be well founded upon any other evidence than that of ray own senses : the statement is nevertheless most per- fectly correct. I could add an account of a great many more experiments and observations which were made with other varieties of dogs and upon other species of animals, but as all the facts which I have noticed are confirmations of the truth of the conclusions which I have drawn from those above stated, I shall state the result of one other ex- periment only, and that solely because it tends to establish a fact which appears to me to be of a good deal of importance. I stated in a communication to this Society many years ago, u upon the Compara- tive Influence of the Male and of the Female Parent upon the Offspring of some Spe- cies of Animals,” that in cases where nature intended the offspring to accompany its parent in flight at an early age, the influence of the parent of one sex upon the form of the offspring differed very widely from that of the other parent, and that when the fe- male parents were of small size and of a small breed, and of permanent habits, and the male of a large size and large breed, and of permanent habits, the length of the legs of the foetus were given by those of the family of the female parent. I imported some Norwegian Pony Mares with the intention of obtaining cross-bred animals between them and the London Dray Horse ; having satisfied myself that the experiment might be made without danger or injury to the smaller animal. The bodies and shoulders of the cross-bred animals which I have obtained are excessively deep, comparatively with the length of their legs, which remains unchanged, except that the joints, being greatly larger, on account of the greatly increased strength of the legs, and being of the same form, necessarily occupy a little more space. The strength of PROPENSITIES OF ANIMALS. 369 these animals appears to be very great; I believe that they will prove capable of draw- ing, particularly up-hill, as heavy weights as the London Dray Horses, provided that they be made to draw from a proper level ; and I am quite confident that they will prove capable of bearing much more long-continued labour and living upon much less food. The hereditary propensities of the offspring of the Norwegian Ponies, whether full or half bred, are very singular. Their ancestry have been in the habit of obeying the voice of their rider's and not the bridle, and the horse-breakers complain, and cer- tainly with very good reason, that it is impossible to give them what is called a mouth ; they are nevertheless exceedingly docile, and more than ordinarily obedient where they understand the commands of their master. They appear also to be as incapable of understanding the use of hedges as they are of bridles, for they will walk delibe- rately, and much at their ease, through a strong hedge ; and I therefore conclude that the Norwegian horses are not in the habit of being restrained by hedges similar to those of England. The male and female parent appear to possess similar powers of transferring to their offspring their hereditary feelings and propensities, except in cases where mule offsprings are produced. In such cases, I think that I have witnessed a decided prevalence of the power of the male parent. The organization of the Mule, which is obtained by cross-breeding between the Horse and the Ass, is well known to be re- gulated to a much greater extent by the male than by the female parent ; and its disposition is, I have some reason to believe, to a very great extent, given by its male parent. I have noticed this in the Mule which is the offspring of a female Ass. I have seen a few only of these animals, but those which I have seen presented the ex- pression of countenance of the Horse, and were perfect horses in temper, and per- fectly without the sullenness and obstinacy of the more common Mule. The results of such violations of the ordinary laws of nature appear to be very various in different species of animals, and I should not here have introduced the subject, but that the characters of mules have in many instances misled the judgement of physiologists in their estimates of the comparative influence in ordinary cases of the male and the female upon the offspring. Whenever I have obtained cross-bred animals by propagating from families of dogs of different permanent habits, the hereditary propensities of the offspring have been very irregular, sometimes those of the male, and at other times those of the female parent being prevalent ; and in one instance I saw a very young dog, a mixture of the Springing Spaniel and Setter, which dropped upon crossing the track of a Partridge, as its male parent would have done, and sprang the bird in silence ; but the same dog having within a couple of hours afterwards found a Woodcock gave tongue very freely, and just as its female parent would have done. Such cross-bred animals are, however, usually worthless, and the experiments and observations which I have made upon them have not been very numerous or interesting. ... - '' ■ ■ , \ ’ . ■ ■ [ 371 ] XXI. On the Elementary Structure of the Muscular Fibre of Animal and Organic Life. By Frederic C. Skey, Esq. F.R.S. Assistant Surgeon to St. Bartholomew s Hospital. Received June 8, — Read June 15, 1837. The volume of the Transactions of the Royal Society for the year 1817 contains a paper which formed the subject of the Croonian Lecture for that year by Sir Everard Home, in which he endeavours to prove the identity of the muscular filaments with the globules of the blood. To the above paper is appended a plate which exhibits an ultimate muscular fila- ment composed of a string of globules, marked by lateral indentations corresponding to each globule. It was inferred by Sir Everard Home, from the experiments of Mr. Bauer, which appear to have furnished the material for the paper, that an ultimate muscular fila- ment consists of a string of globules of the blood, estimated by Capt. Kater at the diameter of about the -^-gVo-th part of an inch. This opinion of the composition of muscular fibre, which has been, according to Dutrochet, confirmed by the authorities of France, viz. Beclard, Edwards, Prevost, Dumas, and himself, was first opposed by Messrs. Hodgkin and Lister, whose re- searches on the subject were published in the year 1832, in an Appendix to the trans- lation by the former gentleman of Dr. Edwards’s work, De l’lnfluence des Agens Physiques sur la Vie. These authorities were the first to deny the existence of a globular structure, and to assert the uninterrupted continuity of the component parts of the fibre. They proceed to point out a most important distinction “ between the minute structures of the muscles of voluntary motion and those of organic life.” The former, they as- sert, “ are characterized by innumerable very minute, but clear and fine parallel lines or striae, which cross the fibre transversely.” These they conceive to be the distin- guishing feature of true muscle. I shall have occasion again to refer to the valuable though brief observations of Messrs. Hodgkin and Lister on the subject of the mus- cular fibre of organic life. Having had the opportunity afforded me, by the kindness of my friend Mr. Henry Goadby, of testing the truth of the opinions of these eminent physiologists by the aid of his admirable microscope, I beg to lay before the Society the results of some in- quiries confirmatory of these opinions, and to add some new facts which I hope may be not uninteresting to physiological inquirers. The microscope which I have employed is an achromatic instrument, possessing a mdcccxxxvii. 3 c 372 MR. SKEY ON MUSCULAR FIBRE. magnifying power of about 600 diameters, by which the objects are exhibited with remarkable distinctness. In order, however, to accomplish this with the best elfect, 1 have invariably submitted the object to a careful preparation under a smaller mi- croscope, used by Mr. Goadby in his able dissections of the anatomy of insects, on the field of which a minute portion of perfectly recent muscle is placed, which has been detached from the mass by means of a lancet, or a fine pair of curved scissars. This, placed on a slip of glass and immersed in water, is observed to consist of many small fasciculi, which may be separated from each other by two pairs of delicate for- ceps. Of these fasciculi one may be retained, and laid out on the glass with as little violence done to its natural structure as possible. The connecting medium of the whole of the fasciculi, is a finely reticulated cellular tissue, the tenacity of which is great in proportion as the muscle is fresh ; but it may be at all times divided with scissars without injury either to the form, or to the arrange- ment of the layer of fibres to be submitted to examination with the larger microscope. The residue reduced by dissection to a nearly diaphanous state will consist of a single layer of ultimate muscular fibres ; and of these the object thus prepared may contain from twenty to thirty placed parallel to each other, occupying for the most part the same plane, and straight in direction. In obedience to the recommendation of Proschaska, and indeed of most physiolo- gists who have made muscular fibre the subject of minute examination, I have sub- jected the objects I have employed, to boiling and maceration. The result of which has been an increased conviction of the superiority of the perfectly recent fibre. The effect of boiling is that of softening to a considerable degree the cellular tissue, which breaks down readily under the instrument employed, and consequently, the easy se- paration of the fibres from each other. This I conceive to be a positive objection, inasmuch as a large quantity of cellular tissue retains its connection to the individual fibres, from which, in consequence of its unnatural softness, it cannot be disengaged. Each fibre therefore presents a woolly appearance, and is comparatively indistinct ; whereas by the aid of the dissecting microscope, with a little careful manipulation, all the superfluous cellular tissue may be removed from the recent fibre that has not been subjected to this process, in consequence of its unimpaired tenuity of texture, and the fibre exhibits in a very striking degree its natural characters. Nor could I concur in the recommendation of Proschaska : “ Turn lacertus inter duos digitos teritur lender ac premitur donee mollis et pulposus quasi evadat la- certus.” On the contrary, I believe the less violence of any kind employed the better. By a coarse manipulation the fibres may be rendered zigzag or serpentine, but their natural direction I believe to be straight. Each fibre is connected with its fellow by cellular membrane still finer than that which connects the smaller fasciculi, and so transparent when recent, as not to impair the distinct view of the fibre itself when clearly in focus. If this cellular connection be lacerated, the fibres are drawn asunder and become distorted. MR. SKEY ON MUSCULAR FIBRE. 373 The muscular fibres of animal life, possess a very varying diameter, but their average size, and that which largely predominates, may be stated at about ^m^th of an inch ; but they may be found of all magnitudes, from the ^fg-th to the T-^th of an inch. If the object be separated from the mass with a pair of scissars, the extremities of many of the fibres will be compressed and closed, but they retain their natural dia- meters up to the extremity, if separated with a lancet or knife; this therefore is pre- ferable. When the object is clearly in focus circular striae are exposed, crossing the fibre along its whole length (Plate XVII. fig. 1. a.). These were known to and delineated by Leuwenhoek, Muys, Proschaska, Fontana, and others. By the former eminent physiologist they were delineated but coarsely, and as existing at irregular intervals from each other ; and judging from the plate by Proschaska, they were but imper- fectly known to him ; yet he has devoted a large portion of one entire chapter to their description. Fontana’s work, however, “ Sur les Poisons,” contains a beautiful re- presentation of the transverse striae, which both for correctness and for effect cannot well be surpassed. They are seen more or less distinctly in the fibre of animal life in all the examples I have examined, but most distinctly in that of the Ox, the Hog, the Ichneumon Fly, and the Blatta Americana (Cockroach). In the two latter they form prominent and elevated bands, resembling in their magnified form the rings of the human trachea (fig. 2. a b.). Straus states that the muscular fibre of the Me- lolontha vulgaris (Cockchafer) is similarly serrated. The transverse striae are placed closely together, but varying much in thickness and in number, a portion of the length of the fibre equal to its diameter containing from 16 to 25. They sometimes appear uninterrupted in their course across the fibre, and occasionally exhibit the appearance of shorter interrupted lines, which, sur- rounding it, present the aspect of a cylinder of a polygonal form (fig. 1. b.). In the plate of Fontana the striae are represented of each variety in the same object. I believe this appearance, which is both frequent and regular, to arise from violence to the fibre, and to be neither natural to its structure nor dependent on optical decep- tion. This arrangement has given rise to the opinion by Proschaska, that the muscu- lar fibres were polyhedral cylinders. It must be observed, however, that this is not an uniform appearance, but that the transverse strise are more generally arranged in continuous and uninterrupted circular lines around each ultimate fibre. I have re- marked that if great care be taken in the preparation of the object while under the dissecting microscope, this broken arrangement is rarely visible ; and considering the improbability of the co-existence in the living fibre of both the series described, as in- consistent with the simplicity of nature, and the impossibility of converting by any manipulation the interrupted into the continuous and ^interrupted strise, I cannot doubt but that this apparently angular arrangement is due to so many artificial de- pressions of a mutilated j£6re. The regularity of the appearance I conceive to be produced by the connection 3 c 2 374 MR. SKEY ON MUSCULAR FIBRE. which subsists between the circular striae and the longitudinal filaments beneath them, the latter being- connected tog-ether in bands around the tube of the fibre, each band containing- about eight or ten filaments, and the appearance of an angular arrangement of the striae is produced by the partial separation of these portions of the fibre from each other. The uniformity of this separation, of which each fibre is susceptible, appears to warrant its subdivision into these bands, which I propose to name “ Fibrillce these again being subdivided into “ filaments .” If a fibre be partly unravelled, this irregular and interrupted appearance of the striae will be rendered still more apparent (fig. 3.). Of the anatomists whose names I have mentioned, Proschaska has given the most minute description of the transverse striae, and yet judging from the plates attached to his work, “ De Carne Musculari,” he must either have seen them with imperfect microscopic powers, or the delineations by the artist have done injustice to his de- scriptions. It is, perhaps, somewhat remarkable that the striae are not seen with equal di- stinctness, in all the muscular fibre of animal life. When distinct, they present them- selves in the form of well-defined rings, the extremities of which may be distinctly traced, encircling the fibre equidistant from each other, uniform in diameter, and ap- parently elevated from its surface into ridges, leaving depressions between them ; and when a fibre is sufficiently bent to render its convex edge somewhat tense, they very apparently stand out from the plane of the fibres, forming circular ridges around it, and presenting the appearance of a fine serrated edge. When very large they occa- sionally form distinct bifurcations or loops, but pursue their course with the utmost regularity. Although the striae exhibit the character above described, of elevated rings cross- ing the fibre, they present in different examples some variety in appearance. For the most part the dark lines are narrower than the light which alternate with them. Sometimes the dark appear elevated, the light or colourless striae forming the de- pressions. At other times this appearance is reversed, and the elevated striae appear to be formed by the intervals between the darker lines. It is not easy to determine the question by tracing these to the margins of the fibre, because the entire fibre is not in focus at the same time, and the slightest move- ment of the field of the microscope distracts the eye from the point of observation. After adopting various modes of inquiry which led to no satisfactory conclusion, accident ultimately convinced me that the opinion I at first entertained was erroneous. I obtained a fibre, torn in the longitudinal direction, in which it was evident that the lines of separation corresponded uniformly with the dark striae, the light, although distorted from their straight direction, remaining- unbroken, and pursuing a distinctly continuous course across the fibre (See Plate XIX. fig. 5.). I infer, therefore, that the light are the elevated striae, and the dark intervening lines, the depressions. After five years immersion in spirit I find them as distinct MR. SKEY ON MUSCULAR FIBRE, 375 and well defined as in the recent fibre, and I am informed by Mr. Owen that they remain perfectly unaltered in muscular fibre that has been immersed in spirit since the period of Mr. Hunter. With respect to their use Proschaska says, “Nil aliud sunt quain profundiora vestigia a vasis, nervis et filis cellulosis, fibram circumdantibus, et ejus vaginam per- reptantibus impressa,” and Fontana adopts this opinion of Proschaska, while the plates of the two authors bear but a very remote resemblance to each other. I conceive the arrangement of the transverse striee to be much too uniform to warrant the explanation of Proschaska and Fontana, for they are not grooves but positive elevations on the fibre. Nor are they invariably found on the muscular fibre of animal life, of which according to the views of Proschaska and Fontana they ought to be the invariable attendants, and with one exception never on that of organic life ; besides which, as I shall afterwards endeavour to prove, they are three or four times smaller than the globules of the blood themselves, and consequently cannot be destined to the transmission of blood vessels. They appear to hold some relation rather to the integrity of the fibre. In the Pharynx the size of the fibres varies from the -^y^th to the -3-y^-th of an inch in diameter, and here is exhibited the greatest variety in the circular striae. They are invariably large as the fibre is small, while the broader fibres, exceeding greatly the average diameter of 0f an inch, exhibit the most delicate pencilling and as minute as the eye can detect. I have once observed them varying in size on the same fibre (Plate XVII. fig. 4.). Is it probable, therefore, that they are destined to the purpose of conveying vessels or nerves, or that they are mere cellular threads ? Throughout the general system of animal life, and except in the Pharynx, the circular striae are most prominent in the large and well-formed fibre, the completeness and integrity of which is its most cha- racteristic feature. If a portion of muscle, which has degenerated by disease and consequent inaction, be submitted to observation, it will exhibit the outline of the fibres without any trace of the striae or longitudinal filaments ; little, indeed, remains beyond the mere form of the fibre. I have examined the gastrocnemeus and soleus muscle of a person for many years bedridden, in which these muscles were wasted to a whitish mass, little exceeding in diameter that of their own tendons. The striae appear to bind together the united strands of the fibre, retaining them in position around the cylinder ; they are the woof to the warp of the longitudinal filaments, but instead of being interlaced with them they form circles around, and attached to the most prominent part of the longitudinal filaments to which they are intimately united. The Filaments or Longitudinal Striae. I have retained the name of fibre to that division of a fasciculus, which though ex- tremely minute, is apparent to ordinary vision. 376 MR. SKEY ON MUSCULAR FIBRE. But each fibre is a compound structure, and is surrounded externally by the cir- cular striae I have above described. A fibre may be reduced to its apparent elements by a successful manipulation, which will exhibit its ultimate structure, composed of a series of longitudinal lines or filaments, placed parallel and in close apposition to each other, around the axis of the tube of the fibre. These are the ultimate known filaments of muscular texture, and of which each fibre of the diameter of -^n^th of an inch contains from 90 to 100. They may occasionally be separated from each other, forming a sort of tasselJed or brush-like extremity of the fibre they compose. Their diameter I conceive to be about the -^yygth part of an inch (Plate XVII. fig. 3. c c.). I have examined these filaments with great care, and with a magnifying power, nearly 200 times greater than that employed by Sir E. Home and Mr. Bauer, and I am compelled to differ from these gentlemen in favour of the opinion, first promul- gated by Messrs. Hodgkin and Lister, that they are ?minterrupted threads or cylin- ders, and neither composed of the globules of the blood, nor possessing even a glo- bular arrangement. I have carefully compared a filament magnified by 600 diameters with the plate by Sir E. Home in the Transactions of the Society, and I find that neither the human filament nor that of any animal in which I have observed it, is nearly so large nor so distinct as that represented in the above plate. Yet Mr. Bauer’s magnifying power was 200 diameters less than that of Mr. Goadby’s which I employed. Be- clard, M. Edwards, Prevost, Butrochet, and Dr. Grant, have adopted this view first promulgated by Sir E. Home. Fontana, who has delineated the fibre of muscle so accurately, and who applied a single lens of -gUth of an inch focus, asserts them to be cylinders, hollow or solid, and only occasionally presenting a globular appear- ance. It should be particularly observed that the circular striae which surround each fibre are closely adherent to the most projecting surface of each longitudinal fila- ment. These latter, when detached into separate shreds, occasionally exhibit on their surface, the marks or indentations corresponding to the distance between the circular strife on the whole fibre (fig. 3. d d.), and I think the filament will present the more or less distinct appearance of a globular structure in proportion to the distinctness of the circular striae. In the Haddock and the Cod, the fibres of which are very large, and in which the circular striae are of extreme beauty and delicacy, the ultimate filaments present no appearance of a globular arrangement, but are distinctly continuous and uniform throughout their whole length. Probably the best test to which they can be submitted is that of placing the glo- bules of the blood and some muscular filaments, under the field of the microscope at the same time. When subjected to this mode of inquiry, the filaments will be ob- served to be excessively minute, and the globules of the blood may be seen floating between and behind the different fibres, in the apparent breadth of about twelve to MR. SKEY ON MUSCULAR FIBRE. 377 a single fibre, and from three to four times larger than the reputed globules of Sir E. Home and Mr. Bauer (Plate XVII. fig. 5.). I have counted on making a successful division of a fibre about 100 filaments, the number mentioned by Leuwenhoek, somewhat less than the half of which were in focus at the same time, those of the opposite side being brought into view, by a new adjustment of the microscope. A single globule suspended behind a separated fibre, would correspond to the breadth of about three filaments. Now the estimate of the diameter of a globule of blood by Dr. Wollaston and Captain Kater is the W-oo-lh part of an inch, from which the above calculation does not materially differ. A more recent admeasurement by M. Edwards * gives them a diameter of -g-l-th of a line. A single muscular fibre has a diameter of of an inch. A single globule of blood, which is about the twelfth part of the breadth of a fibre, T-Anrth of an inch. If each fibre contain 100 filaments, something less than the transverse breadth of the fibre, or forty, or allowing for the receding margins multi- plied by 400, is 16000, which is the breadth of a single filament. A globule of blood to the diameter of a filament is therefore as 4800 to 16000. If this calculation make any approach towards truth, the filaments cannot be composed of the globules of the blood, and they are not identical. I believe the appearance of globules, of which the filaments are asserted to be com- posed, is due to the delicate indentations of the transverse striae upon them, for the distinctness of the globular appearance is always proportionate to that of the trans- verse striae. I was, therefore, very desirous of examining the appearance in the fibre of an animal characterized by delicacy of the striae, and I found that in the Cod and the Haddock, in which they are most minute, the filaments being disencumbered of their connection to the cross bands or striae, pursue their course floating and twisted in all directions, without a trace of a globular appearance or mark of any kind, cylin- drical, and of uniform thickness throughout. Glutinous interior of the fibre . The interior of each fibre appears to contain a glutinous semitransparent substance, covering thickly the inner surface of the longitudinal filaments. It is very soluble in water, and when the end of a fibre is broken up, exhibiting its filamentous struc- ture, no trace of this substance is seen, but it is apparent on the internal surface of each fibre when the tube is exposed. It is this glutinous coating to the interior of the tube, that conceals from view in a degree the long filaments of the opposite sur- face, when that part of the fibre is brought into focus. Tube of the fibre. The divided extremity of each fibre presents the appearance of a jagged circle ter- minating an apparently hollow tube. For the most part these extremities are con- * Encyclopedia of Anatomy and Physiology. 378 MR. SKEY ON MUSCULAR FIBRE. tracted, and are occasionally elongated even to a point. Frequently, however, the fibre retains its natural diameter up to its termination in the jagged circle (Plate XVII. fig. 1 . c.). This part of the fibre will occasionally exhibit an orifice, such as would appear by the foreshortening of a tube cut obliquely. When a section of the fibre is made in the vertical direction, this appearance is not observed. It is difficult to obtain a distinct view of the tubular end of a fibre by any careful preparation of the object, but ivithout such preparation several fibres in the same ob- ject, may exhibit its tubular character. If such a fibre be brought into focus at its extremity, the circular striae and longitudinal filaments will be exposed, extending to the near margin, and if the depth of the fibre be then penetrated by the microscope, the longitudinal filaments of the opposite side will be jirst exposed, and secondly, the circular striae, but neither of these will be distinct, being obscured by the glutinous lining of the interior of the tube. A careful adjustment will thus detect the aperture of the tube of the fibre, which appears in the form of a hollow cylinder, perfectly translucent in its centre, but less so at its sides from their vertical direction to the plane on which they rest. The latter present when in focus the dark outline of the fibre, extending along its length. If a single fibre be divided in the longitudinal direction its cavity may be exposed along a considerable length, the filaments composing the fibre with their investing- striae of the opposite side of the cylinder may then be seen when the near side is out of focus (Plate XVIII. fig. 1. a.). As the tubular character of muscular fibre is not always distinctly apparent, I would add the following arguments in favour of this view of their composition. 1st. A fibre is frequently elongated to a point, up to the extreme external surface of which, the circular strise are apparent. If the fibre be a solid cylinder, what be- comes of the central substance ? for it is evidently the external surface that is so atte- nuated, indicated by the presence of the circular striae. 2nd. When a fibre is entirely separated into its filaments forming a fringe-like ex- tremity, that surface of the fibre nearest the eye, forms all that portion of the fringe which is distinctly in focus. If the focus be then changed the fringe of the opposite side is brought into view, but there is no middle fringe to complete what would then be, a solid tassel (Plate XVII. fig. 3.). 3rd. If a few fibres be placed on glass and dried, little remains apparent, beyond the black outline of each fibre, their central portions become obliterated, and conse- quently the fibre is transparent. If the margin of the fibres are rendered dark by their perpendicularity to the plane below them, a fortiori, the middle portion of the fibre ought to exhibit the same phenomenon, for it is higher from the surface and consequently thicker. 4th. The separation of a few or more filaments from the body of a fibre, never ex- hibits a second layer of filaments beneath them. This view of a central filament might reasonably be expected if each fibre were composed of a solid cylinder ; and MR. SKEY ON MUSCULAR FIBRE. 379 it would be interesting to ascertain the relation which subsists between the central filaments, supposing the fibre to possess them, and the transverse strise. I have never seen any appearance like that of filaments projecting from the inte- rior of the fibre at its extremity ; for although the exhibition of the tubular character may be rare, involving as it does many conditions, yet it is not unreasonable to ima- gine, that if the fibre were solid, the extremities of the central filaments would be occasionally as apparent, as those which are arranged on its external surface. 5th. Analogy to other structures would enable us in some degree to comprehend the utility of the circular strise, supposing them to surround a tube which they pro- bably compress in certain states of its action. Are th o, filaments like the fibres which they compose tubular ? Up to a late period of my inquiries into this subject, I had only the ground of ana- logy to support the opinion of the tubular character of the filaments, but being engaged in examining the muscular coat of the trachea of a Horse, I was not a little gratified to observe the very apparently tubular composition of these threads, one of which, indeed, placed at right angles to the plane below it, exhibited its cavity to some distance within (Plate XVIII. fig. 2.). Indeed the filaments presented very much the aspect of miniature fibres, in which I could almost fancy I saw some traces of still minuter threads. This though speculative is, I think, not very improbable ; but of the tubular nature of these delicate threads, I have no doubt; they were distinctly perceptible to many observers. From the above I deduce, That the human muscular fibres of animal life possess an average diameter of -^y^-th of an inch. That they are surrounded by circular striae varying in thickness and in number. That the striae are actual ridges or elevations on the fibre, leaving depressions be- tween them, considerably smaller than the globules of the blood. That each fibre is divisible into bands or fibrillae, which, composed of many ulti- mate filaments are arranged in parallel longitudinal lines around the axis of the fibre, and that the partial separation of these fibrillae produces the occasional broken or interrupted appearance of the circular striae. That each band or fibrilia is subdivided into filaments, of which every fibre of -Hr-g-th of an inch diameter contains about 100. That the muscular filaments possess a diameter of about the third part of a globule of the blood, or -rg \-6 0th of an inch, and that they are tubular, and that these fila- ments are arranged longitudinally around the tube of the fibre, which finally contains a soluble gluten. The human fibre of animal life pervades the whole of the external muscles, and all internal muscles connected to any form of tendinous matter. This will include those of the tongue, palate, larynx, and pharynx, with some portion of the oesophagus pro- longed from it, and constituting an exception to this rule ; the muscles of the orbit 3 D MDCCCXXXVII. 380 MR. SKEY ON MUSCULAR FIBRE. and ear, diaphragm, intercostals, levator and sphincter ani. The muscles of the tym- panum incased in bone, composed so largely of tendinous matter, and apparently be- yond the reach of voluntary power, must however be classed among the muscles of animal life. Yet they are so intermixed with tendon, that had I not rendered myself familiar with the structure and appearance of tendinous fibre, which possesses a re- mote resemblance to the muscular fibre of organic life, I should have erroneously concluded that they belonged to that class. They possess, however, all the charac- ters incidental to the fibre of animal life. Organic Life. The microscopic view of the muscle of organic or involuntary life exhibits a struc- ture essentially different from that of the fibre of the external muscles. The difference was first made known by Messrs. Hodgkin and Lister, who state that “ the minute fibrillee which enter into the composition of the fasciculi of fibres of which this tissue is made up, instead of presenting the transverse striae, are per- fectly smooth, and appear to be continued to a considerable length, of nearly uniform width.” They describe the fibre as nearly straight and parallel, occasionally inter- lacing and dividing among themselves. In the muscular fibre of organic life there are no distinct and separable fibres, no transverse striae, with one exception, and no appearance of the larger tubes. This tissue appears to consist of a series of irregularly disposed lines of various thickness, taking for the most part a longitudinal direction, and forming a kind of untraceable net-work difficult of delineation. Although there exist no single fibres connected by cellular tissue with others around it, yet there is no difficulty in obser- ving the direction of the muscle ; for the lines take one course, frequently, however, bending to one side and uniting with others around : but the aggregate, though far from straight, pursue one general longitudinal direction (Plate XVIII. fig. 3.). The cut margin of the object exhibits no projecting fibres, which in the process of prepara- tion have started out from their connection with others, or which have evaded the straight division with the knife ; but the whole edge is smooth and uniform. The drawing is taken from the fibre of the small intestine (jejunum). The muscle of organic life appears to possess a smaller proportion of cellular tissue than that of the voluntary muscles. None is required for the connection of fibres, for in reality there are no fibres in the muscle of organic life, which rather consists of filaments interwoven with each other to form the general structure, than arranged in parallel lines around the cylinder of each separate fibre, as observed in the mus- cular fibre of animal life. I could imagine it might be artificially imitated by subjecting a thin layer of these latter fibres to a degree of pressure which would destroy the integrity of each fibre, and yet preserve the general direction of its filaments. It may be readily distin- guished from tendinous fibre, in which the filaments are uniform in size, pursuing MR. SKEY ON MUSCULAR FIBRE. 381 individually one unvarying line, each filament being parallel to those around it. This great regularity in arrangement renders tendinous fibre a microscopic object of singular beauty and delicacy, when it has not been subjected to a coarse manipula- tion (Plate XVIII. fig. 4. b.). To the general description of the muscular fibre of organic life, the heart forms an important exception (Plate XVIII. fig. 5.). It appears to possess a somewhat compound character of texture. There is a nearer approach to the fibres of animal life, each fibre being more distinct than those of any other internal viscus, and possessing a very delicate pencilling of transverse striae , as observed by Hodgkin and Lister. The fibres are only about one third of the magnitude of the animal fibre of the same subject ; they are interwoven with each other, and being more separable than the general fibre of the other organic viscera, project at the cut extremities, where their diameter is very apparent. The net-work which they form is composed of the entire fibre, and not, as in organic life in general, by the filaments of each. The examination of the pharynx, composed of the fibre of animal life, and that of the oesophagus of organic life, exhibited some views of considerable interest. This continuous line of tube commences in animal, and ends in organic fibre. I was de- sirous of ascertaining the nature of the junction, whether by a gradual blending of one description of fibre into the other, or by an admixture of the two. The constrictor superior, the first agent of deglutition, exhibits the perfect fibre of animal life. The striae are of ordinary size, of about 24 to the diameter of the fibre. Those of the constrictor medius exhibit no peculiarity, except that they are strongly marked and distinct ; but the cellular tissue is dense, possessing the character of that connecting the texture of organic life. The same observations will apply to the constrictor inferior, in which the density of the cellular tissue is yet perhaps greater. The structure of the first 2 inches and half or 3 inches of the oesophagus is that of animal life, but surrounded with striae varying much in number and in breadth. The size of the fibres themselves, likewise varies considerably, and may be found from that of the 700th to the 300th of an inch diameter (Plate XIX. fig. 1.). I have generally observed that the smaller fibres possessed the larger striae. These frequently ap- peared to bifurcate in their course around the tube, and at the edge distinctly pro- jected from the surface, forming the serrated appearance I have previously described. The larger the fibre the more delicate are the striae, which become less and less ap- parent on the larger fibres, as they descend on the oesophagus. Still the smaller fibre with large striae may be found as far as the fibre of animal life itself exists, and this junction of the two takes place at about 3 inches from the lower border of the constrictor inferior, where both structures are associated in the same object. One half inch below, and the fibre of animal life ceases entirely, and it is at this precise point that the oesophagus enters the cavity of the chest. Perhaps the most interesting, as well as the most instructive object exhibiting the muscular structure of organic life, is that of the arterial system, the composition of 3 d 2 382 MR. SKEY ON MUSCULAR FIBRE. which has presented material of the deepest interest to all physiologists of the last and the present century. If a portion of the middle coat of an artery, whether of the pulmonary or aortic system, be submitted for examination, it is impossible to distinguish it from the mus- cular texture of the stomach, intestinal canal, or bladder. It exhibits the perfect composition of the organic muscular texture of these parts (Plate XIX. fig. 2.). It would be impracticable to determine, with so large a microscopic power as that which this subject demands, the relative proportions of muscular fibre in the larger, compared with that in the smaller arterial tubes ; but I have observed that the mus- cular texture of the smaller vessels, as the internal mammary and the smaller branches of the iliacs, is paler and of a more delicate fabric, but their relative proportions could only be appreciated by a different mode of inquiry. I need hardly state, perhaps, that the fibres are placed circularly around the ves- sels, and that the muscular, forms the thickest of the coats of these tubes. I can discover no resemblance between the structure of the middle coat of an artery and that of the elastic ligamentous tissues of the body. If the drawing of the former be compared with that of the muscular fibre of or- ganic life in general, I think it will be found so closely to correspond as to appear almost identical. Possibly the arterial tissue is more delicate, but both apparent composition and arrangement are the same. I observe, however, no comparison between the arterial tissue and that of the elastic ligamentous structures. These latter are composed of large and distinct filaments placed in a parallel direction, and connected by dense cellular tissue. Each filament possesses its characteristic property of elasticity, and when separated at one extremity from the mass it curls backwards on itself. The entire structure is likewise more transparent than the arterial tissue, and is much more simple in its arrangement (Plate XIX. fig. 4.). I have been unable to detect anything approaching to the character of muscular fibre in the structure of the venous system in general. I have observed it, however, in the hepatic veins of the Seal ; and it doubtless exists in all animals subject to an arrest of the venous circulation around the heart. There yet remains a structure in the economy which presents an interest little in- ferior to that of the arterial system, I mean the iris. The tenacity of this membrane is greater than that of any other structure I have examined, so much so, as to render it exceedingly difficult of preparation under the dissecting microscope. When exhibited with the larger power it presents so much the character of the muscular fibre of organic life, that I feel almost inclined to associate it with that system. As regards the arrangement, I have less doubt than I have of the chemical compo- sition of the iris, which does not possess the semitransparent character of jibrine. MR. SKEY ON MUSCULAR FIBRE. 383 Yet there exist some important distinctions, which require considerably more exten- sive observation than I have hitherto been able to make ; and I am anxious not to commit myself by the expression of an opinion hastily formed as to its composition, on which my limited inquiries have hitherto fallen far short of the difficulties of the subject. It is difficult to explain the experiments of Sir E. Home as regards the muscular texture of the stomach which he employed, and which is of the pure structure of or- ganic life. I have examined each part, and I have been unable to obtain the least trace of animal fibre. The ultimate muscular filaments may be seen in the texture of organic, but with by no means the distinctness of animal life, in consequence of its reticulated structure which renders them difficult of separation from the bulk of the fibre. The muscle of organic life pervades the greater part of the oesophagus, the stomach including that of the ruminants and the alimentary canal, the trachea and bronchial tubes, the uterus , the urinary bladder, the arterial system, and possibly the iris. The diameter of all muscular fibres holds a relation to age, being in the human foetus, as well as in the young of all the animals in which I have observed it, about one third the diameter of that of mature age (Plate XIX. fig. 3.). On comparing the muscular fibre of animal and organic, or voluntary and invo- luntary life, it does not appear surprising that there should exist the remarkable va- riety of structure which I have described. Although both systems are embraced under the general denomination of muscle, and possessing the characteristic property of irritability, yet their functions in the economy are so distinct, and the power re- quired by each is so unequal, that we might almost have conceived the existence of an important difference of structure. In the muscle of animal life we find the fibres with their subordinate filaments pur- suing a direct course between the attachments of the whole muscle, or deviating from it merely for the purpose of a convenient adhesion to its common tendon. Hence the advantage obtained by a united and cooperating force, by which the whole component fibres of the muscle are called into action at the same time. The fibres possess no independent influence, but all cooperate to one obvious end, that of ap- proximating the extremities of the muscle, and act with a force which, considering the nature of their general adaptation, may well be deemed enormous. But the power of the muscle of organic life is limited. We find it spread over ex- tensive tubular surfaces of membrane, and contributing to the involuntary functions of internal life, by a slow and gradually extending contraction. It has no antagonist but the contents of the tube it surrounds, its influence on which extends along the surface of the muscle, as the contents descend within the tube. By means of its matted structure it serves the purpose of a nearly complete invest- ment to the canal it surrounds, while its connecting and reticulated composition enables it at once to transfer the contents of the tube within the influence of the 384 MR. SKEY ON MUSCULAR FIBRE. portion prolonged from it, and to communicate the stimulus necessary to their re- moval. To this function the heart again forms a striking exception. Its contractions are impetuous, and throughout each division of the organ simultaneous. In the heart therefore we find the modified but separate fibre of animal life, with all the physical characters indicating great contractile power, demanded for the important function it is known to possess. Charterhouse Square, January 10, 1837. Explanation of the Plates. PLATE XVII. Fig. 1 . a. An unbroken muscular fibre of animal life, with continuous striae, mag- nified about 600 times, linear measurement. c. Its tubular extremity. h. A similar fibre broken into fibrillae, exhibiting the interrupted striae, and presenting a polygonal appearance. Fig. 2. a h. Muscular fibres of animal life, from the Cockchafer. Fig. 3. A muscular fibre separated at its extremity into its component filaments. a, a, a. Striae continuous across the unbroken fibre. b, b. The fibre broken into fibrillae, forming the interrupted striae. c, c. Muscular filaments forming a tasselled extremity to the fibre. d, d. Filaments retaining slight marking of the striae. Fig. 4. Circular striae varying in size on the same fibre. Fig. 5. a, a. Filaments ; globules of blood floating behind them, showing their re- lative diameters. Fig. 6. Globules magnified 600 times. PLATE XVIII. Fig. 1. a. A tube cut open longitudinally, magnified 400 times, linear. b. General arrangement of fibres, magnified 200 times, linear. Fig. 2. Muscular fibre of organic life from the trachea of a Horse, showing the tubular character of the filaments. Fig. 3. Muscular fibre of organic life (Jejunum). Fig. 4. a and b. Tendon; tendon of Pectoralis major muscle. •/Jttusis'c-, ItiJt MD(xxmvi i nx'j 1 1 L/. , w Jficusire, blh, .w.MDCCCHIW.111/ 383. Jfy- / J.Jtaju-', Uih MR. SKEY ON MUSCULAR FIBRE. 385 Fig. 4. b. Tendon of Tensor tympani muscle, with a single muscular fibre. Fig. 5. Heart (human), composed of distinct fibres, with a few circular striae. PLATE XIX. Fig. 1. Muscular fibre taken from the human oesophagus, about three inches below the pharynx, showing the two structures of animal and organic life com- bined. Fig. 2. Middle coat of an artery. Fig. 3. Foetal fibre of animal life, magnified 300 times, linear. Fig. 4. Ligamentum nuchae of the Sheep. Fig. 5. A fibre of animal life torn longitudinally, exhibiting the separations of the dark striae, the serrated margins being due to the elevations of the light striae. Fig. 6. Middle coat of an artery. - ■ .. [ 387 ] XXII. Observations on the Minute Structure of some of the higher forms of Polypi, with views of a more Natural Arrangement of the Class. By Arthur Farre, M.B. Lecturer on Comparative Anatomy at St. Bartholomew' s Hospital. Communicated by Richard Owen, Esq. F.R.S. Received May 11, — Read June 8th and 15th, 1837. To attempt the reformation of any class in the animal kingdom, — the numerous individuals of which are widely spread over the surface of the globe, many therefore difficult of access, and others, though easily obtained, yet extremely perishable, and for the most part so minute, as to require for their examination the utmost pene- tration of the microscope and unwearying perseverance in the observer — is a task of no little difficulty in the accomplishment, and one that may fairly entitle him who enters upon it to expect to meet with indulgence. It is probably owing to these retarding circumstances that the class Polypi, as now generally understood, presents such a heterogeneous accumulation of widely dif- fering structures as is perhaps to be found in few similar portions of the animal king- dom : and it is only by a strict investigation of the intimate structure of the various forms of animals that have been so indiscriminately heaped together, that any per- manent arrangement that shall indicate their true and natural affinities may be hoped for. The slightest glance at the history of the revolutions which the ideas of naturalists have undergone, with reference to this class since it first became known, will esta- blish the truth of this position, and show the importance of attending to the entire organization of the animal, as far as it can be known, in any attempt at classific arrangement. It is not wonderful, indeed, that a class of animals to which the name Zoophytes has been so long and universally applied, a name sufficiently expressive of the dubi- ous position which they were supposed to hold in the kingdom of nature, should by the earlier naturalists have been referred entirely to the vegetable or even to the mi- neral kingdom ; and accordingly we find that in the seventeenth century many of these were described as minerals by Boccone and Guison ; and by Cesalpin, Bauhin, Lobel, Tournefort and Ray as vegetables ; the great quantity of earthy materials, produced by many forms of Zoophytes, leading to the former supposition and giving rise to many theories, as to the growth of stones, &c. ; whilst the more obvious ex- ternal characters and habits would, under deficient means of observation, readily favour the latter. And this supposed alliance with the vegetable kingdom seemed to 3 E MDCCCXXXVII. 388 DR. A. FARRE ON THE STRUCTURE OF THE CILIOBRACHIATE POLYPI. be still further strengthened when, in the commencement of the following century, the animals of some species of coral were described by Marsigli as flowers. This circumstance perhaps more than any other tended to confirm botanists in claiming these bodies for the vegetable kingdom, notwithstanding that it was main- tained by chemists that their structure exhibited more of an animal than a vege- table nature, and that even so early as the sixteenth century the animals of several had been distinctly described as such by Imperati. The discoveries and opinions, however, of this observer, who appears to have been the first to ascertain the animal nature of these Zoophytes, as well as the observations of Rumphius made upon many of the living corals in the Archipelago, seem to have been entirely neglected and forgotten ; nor does it appear that the botanical theory was disturbed until a similar discovery to that of Imperati was communicated to the Acad, des Scien. in 1 727 by Reaumur, founded upon the observations of Peysso- nell, who maintained that the supposed flowers of Marsigli were in fact aggregate animals analogous to Actinia, which latter animal was then, perhaps, the only one of the class to which a vegetable nature was not generally ascribed. This communication seems to have directed the attention of naturalists more im- mediately to the subject, and the subsequent discoveries of Trembley of the naked Polypi, in 1740, and the investigations of Bernard de Jussieu, Guettard, L^efling and Donatt, were greatly instrumental in pointing out the true nature of Zoophytes. But by none was the investigation pursued to so great an extent as by the indefati- gable Ellis, whose systematic work was the first of the kind that appeared upon this subject. In maintaining the entire animality of Zoophytes Ellis was strongly op- posed by Linnaeus, Baster, and Pallas, who still holding an opinion midway between the two that divided naturalists, maintained that they were of a mixed nature, partly animal and partly vegetable. With Linnaeus, however, and his contemporaries this view of the subject ceased, and subsequent investigations have completely exposed the fallacy, both of the vege- table and vegeto-animal theories. But the work of Ellis, as well as that of Pallas on the same subject, can be considered as but little more than a classification of the more solid, or least perishable, and least important parts, (the part called Polypary by Reaumur), without reference to the structure of the individual animals, which was then little understood, and was generally supposed to partake in all these cases of the simple nature of Hydra, and they were therefore so called by Linnaeus. This mode of classification, by no means likely to lead to a natural arrangement of the subject, was from the same cause adopted in the more recent systems of La- mark and Lamouroux, where the characters of the axis or polypary are again taken as the basis of arrangement ; though a considerable advance is made in founding se- condary divisions on the structure and form of that part of it, which is imme- diately inhabited by the individual animals, commonly called the cell. Still, how- ever, from a deficiency of knowledge the most important parts are disregarded, and DR. A. FARRE ON THE STRUCTURE OF THE CILIOBRACHIATE POLYPI. 389 animals frequently united even in the same genus which have not a classical rela- tionship. But Renier and Savigny had already shown that the animals of Botryllus and Alcyonium, Linn., were not, as had been generally supposed, Polypes, but possessed a structure similar to that of Ascidia ; whilst the descriptions and figures given by various writers of some of the cortical Polypes showed that these were closely allied to Actinia. But though some of the larger forms had been thus more accurately investigated, the hundreds of minute species that remained must necessarily have escaped obser- vation, until the more general use of the microscope and the great improvements lately made in that instrument, opened up a wide and almost entirely new field of dis- covery, which the inefficient instruments of previous investigators had only just enabled them to enter upon. By this means the currents observed by Spallanzani to be produced by some of these animals, and attributed by him to the action of the arms, were shown by Stein- buch* * * §, by Fleming-}' in Valkeria, and by Grant^ in Flustra, to be due to the vibra- tion of cilia, by which the sides of the tentacula were fringed ; and to the last-men- tioned naturalist we are also indebted for many important observations on the ciliated reproductive gemmules of this family, on the form and growth of the cells, and on the digestive cavity. It was shortly after discovered by Milne Edwards and Audouin that some of these compound polypes possessed an anal as well as an oral opening to the alimentary canal ; a discovery which Edwards communicated to the Acad, des Sciences in 1828 §, and proposed thereupon to found a division of the class Polypes into different families, according to the forms of the alimentary canal. In this class, however, he also in- cludes Sponges. A similar discovery was also made about the same time by Ehrenberg, indepen- dently of that of Edwards, and was taken by him as the basis of his classification of Polypes ||, dividing these animals into two principal groups, Anthozoa and Bryozoa, according as the alimentary canal has one or two external openings; a division which he has since (1835) modified by separating the Sertularim and other hydriform Po- lypes, which form a third group denominated by him Dimorphsea. This type of structure, observed shortly after (in 1830) by Thompson^ in Ireland, * Analecten Neuer Beobachtungen und Untersuchungen fur die Naturkunde 1802, p. 89, quoted by Dr. Sharpey, Cycl. Anat. art. Cilia, p. 609. f Mem. of Wern, Soc. Fol. Part V. p. 488. + Edinburgh New Philosophical Journal, vol. iii. 1827. § Resume des Recherches sur les Animaux sans Vertebres, faites aux iles Chaussay, par MM. Audouin et Milne Edwards. Annales des Sciences Naturelles, t. 15. Sept. 1828; and Recherches Anatomiques, Phy- siologiques et Zoologiques sur les Eschares, par M. H. M. Edwards. Ib. t. 16. Juillet 1836. 0 Symbolae Physicse. Zoological Researches and Illustrations, Memoir V. Cork, 1830. 3 E 2 390 DR. A. FARRE ON THE STRUCTURE OF THE CILIOBRACHIATE POLYPI. apparently without a knowledge of the discoveries of Edwards and Ehrenberg, was described by him as indicating a new form of animal, to which he applied the name Polyzoa, to distinguish them from such of the compound animals as partake of the nature of Hydra, and he proposed to elevate them to the class of tunicated Mollusca. The existence of this type in Flustra has also been since demonstrated by Mr. Lister, in his paper on “ Tubular and Cellular Polypi,” communicated to the Royal Society in 1834; which contains also much new and valuable information relative to the economy of the more simple or hydriform Polypes. The descriptions and illustrations of these last-mentioned observers are in various degrees confirmatory of each other, and are sufficient to indicate in a general way the characters of this more recently discovered form of animal ; but the uses of their various organs are often confused and misunderstood, and their minute structure certainly not investigated with that degree of accuracy which it deserves, and which the present state of science demands. It is with the view of supplying these deficiencies that I am induced to lay before the Society the result of my own observations upon this very interesting portion of the animal kingdom, conceiving that they have been prosecuted to an extent that has not hitherto been effected. My attention was first particularly directed to the subject in the year 1835, during a short visit to the Isle of Sheppy, for the purpose of exploring the various animal productions, so abundant on that portion of our coast. During this visit the type of structure here referred to came under my notice, and the results of my investigations upon it were then so entirely new to me, that I was induced to repeat these visits at intervals ; and upon the specimens thus procured, and also upon similar supplies obtained from the same place, which I have repeatedly received from my friend Mr. Bowerbank, I have been enabled to continue the investigation beyond the limits that a mere temporary visit to the coast would have enabled me to do. During the early part of these investigations I was but little acquainted with the observations that had already been made by others upon the subject. But having since been necessarily led to consult these, I find some of my own investigations in various degrees confirmed. Those points therefore that are not new I have either wholly omitted, or touched upon only to the extent that would be necessary to render the subject intelligible. The facts that I have thought the most interesting and important to be stated are embodied in the descriptions of the various species that furnish the subject matter of the present memoir. Two of these species I believe to be entirely new, and I have ventured to name them accordingly. A few particulars with regard to the method that I have pursued may not be without their use, though each specimen will frequently require a different manipu- lation. A number of glass troughs being at hand (which with the aid of a little cement DR. A. FARRE ON THE STRUCTURE OF THE CILIOBRACHIATE POLYPI. 391 may be easily constructed of every variety of depth), these should be filled with sea water, and a specimen of the species to be examined placed in each, care being- taken to adapt the depth (from side to side) of the trough to the thickness of the specimen, it being very desirable that no more water should intervene between the latter and the sides of the glass than is just sufficient for the purpose. If the specimens are tolerably recent it will seldom fail that in a short time the animals, which always contract the instant that they are disturbed, will begin to ex- pand themselves, in which state many may be observed by the naked eye, and a very cursory glance under the instrument will then show which are the best adapted for observation. For this purpose it is necessary that a clear reflected light should be transmitted through the object, care being taken to avoid all artificial light, which is totally in- adequate to supply that delicate and perfect definition requisite for the examination of objects so extremely minute as those which form the subject of the present essay. This method, which if rigidly pursued, greatly limits the time during which the in- vestigation may be continued, is yet the only one that can be safely trusted to ; and for subjects of this nature I have therefore long ceased to use any other than a clear daylight*. The figures which are added in illustration were drawn from the specimens by being previously outlined by the aid of a camera lucida attached to a reserve eye- piece, to allow of its being instantly substituted whenever a favourable specimen should present. By this means a faithful record of appearances is preserved that cannot be equalled, and indeed hardly obtained by other means, although it is scarcely in the power of a drawing to convey an adequate idea of the exquisite^ beauty of the living objects. PLATE XX. and XXI. Bowerbankia densa^f, Mihi. Fig. 1. Found commonly on Flustra foliacea, thickly aggregated in masses of half of an inch to one inch diameter. * The very perfect instrument, in the possession of my brother, with which I have been enabled to make these observations, was constructed by Mr. Ross, of London, to whom the greatest credit is due for the perfec- tion to which he has brought his glasses. + This I believe to be either entirely new, or to have been confounded with the Grape coralline of Ellis, (Corall. pi. xv. f. 25. c. C. D.) the Valkeria uva of Fleming (Brit. Anim., p. 551. gen. lxx. 197.), &c. What- ever be the animal meant by Ellis, it certainly differs materially from the present species, which I cannot refer to any described genus with which I am acquainted. Believing it to be new I have named it after my friend Mr. Bowerbank, whose zeal displayed on this as on many other occasions where the study of natural history may be promoted, was mainly instrumental in inducing me to follow up these investigations, on account of the many supplies that I received from him, and I gladly therefore take the opportunity of acknowledging and re- cording the obligation that I am under to him. 392 DR. A. FARRE ON THE STRUCTURE OF THE CILIOBRACHIATE POLYPI. Fig. 2. The animal when fully expanded is about one twelfth of an inch in length. In its retracted state it is completely inclosed in a delicate horny cell, sufficiently transparent to admit of the whole structure of the contained animal being seen through its parietes. The cells are connected together by a cylindrical creeping stem, upon which they are thickly set, and sessile, ascending from its sides and upper surface. Fig. 3. a. The animal when completely expanded is seen to possess ten arms of about one third the length of the whole body, each arm being thickly ciliated on either side, and armed at the back by about a dozen fine hair-like processes, which project at nearly right angles from the tentacula, remaining motionless, while the cilia are in constant and active vibration. The tentacula are united together at their base to form a circle, in the centre of which is the mouth, and from which descends the oesophagus (fig. 3. a 1), bulging a little at its commencement, and then contracting and passing down nearly straight to its termination. The parietes of the oesophagus, especially at the upper part, which may be more correctly denominated the pharynx, are thickly studded with minute oval spots, arranged closely in contact with each other (Plate XXI. fig. 8.). The whole organ appears to be highly irritable, and contracts vigorously when food is introduced into it. At the termination of the oesophagus is a distinct cardiac orifice (fig. 3. a 2.) that opens into a small globular cavity (a 3.) of singular construction, which appears to perform the office of a gizzard. The parietes of this organ are thicker than in any other part of the alimentary canal. They contain two dark round bodies placed op- posite to each other, from each of which dark lines are seen radiating. In the space between these two dark bodies may be seen a number of squamiform spots arranged closely in contact, and presenting a beautifully regular tessellated appearance. This appearance was at first supposed to be owing to the crossing of the radiating lines at this point (fig. 4.) ; but a more accurate examination convinced me that they were distinct bodies lining a part of the interior of the cavity, and probably performing the office of gastric teeth : they have a remarkably definite outline when viewed under favourable circumstances, and by tearing open the gizzard, or bursting it by pressure, may be separated from its inner surface (Plate XXI. fig. 7-)- The two dark bodies ap- pear to be the points at which the radiating lines are concentrated. When the organ is in a state of rest and viewed laterally, these are seen projecting into the cavity, and giving it an hour-glass form (fig. 5.) ; but when it contracts these bodies become elongated, and their inner surfaces are closely applied to each other, and the cavity is obliterated (fig. 6.). The alterations in the form of this organ appear to be entirely due to these apparently muscular bodies. They are conspicuous even in animals not yet arrived at maturity (fig. 3. c 1.). This organ, which I shall call the gizzard, opens downward into the true digestive stomach (fig. 3. a 4.), an oblong cavity terminating below in a blunt extremity, and from which it is separated only by the contraction of the parietes. The entire walls DR. A. FAttRE ON THE STRUCTURE OF THE C1LIOBRACHIATE POLYPI. 39,3 of the stomach are thickly studded with spots of a rich brown colour. These appear to be hepatic follicles, and to prepare a fluid that tinges the whole organ, as well as its contents, of a similar hue. From the upper part of the stomach, and by the side of the entrance from the giz- zard, arises the intestine (a 6.), by a distinct pyloric orifice ( a 5.) that is surrounded by vibrating cilia. The intestine passes up straight and narrow by the side of the oesophagus, from which it is entirely separate and free, and terminates by a distinct anal orifice (a / •) in the delicate parietes of the body, close to the outer side of the tentacular ring. The parietes of the intestine are marked with pale spots, something like those of the pharynx, and the whole tube, like the rest of the alimentary canal, possesses a high contractile power. Thus the alimentary canal consists of pharynx or oesophagus, gizzard, stomach and intestine, with subsidiary secreting follicles, and distinct oral, cardiac, pyloric, and anal orifices. The whole floats freely in a visceral cavity, the boundaries of which are formed by the delicate transparent parietes of the animal ; the space between the alimentary canal and the parietes being occupied by a clear fluid, and by the muscles which act upon the animal. That the animal possesses distinct membranous parietes separate from the walls of the alimentary canal, and independent of the cell which it inhabits, does not at first sight strike the observer, but the slightest attention to points hereafter to be men- tioned will place this matter beyond a doubt. The transparent horny cell which closely embraces the body of the animal is nearly unyielding in its lower two thirds, but terminates above by a flexible portion, which serves to protect the upper part of the body when the whole is expanded, in which state it is of the same diameter as the rest of the cell; but when the animal retracts is folded up and drawn in after it, and completely closes the mouth of the cell. The flexible part consists of two portions, the lower half being a simple continua- tion of the rest of the cell ; the upper consisting of a row of delicate bristle-shaped processes or setse, which are arranged parallel with each other round the top of the cell, and are prevented from separating beyond a certain distance by a membrane of excessive tenuity, which surrounds and connects the whole. This mode of termina- tion of the cell is one of constant occurrence, as will be described in other species, and is evidently a provision for allowing of the freest possible motion of the upper part of the body in its expanded state, to which it affords at the same time support and protection. The mechanism by which the acts of protrusion and retraction are effected is some- what complicated, and these acts are usually performed with such rapidity, especially that of retraction, that it was only by perseveringly watching the animals for several hours together, and sketching down each step of the process, whenever I could catch more than a momentary glance of one of them in any intermediate position, that I was at length led to a satisfactory knowledge of the precise mode of performing these operations. 394 DR. A. FARRE ON THE STRUCTURE OF THE CILIOBRACHIATE POLYPI. For the process of retraction two distinct sets of muscles are provided, the one act- ing upon the animal, and the other upon the flexible part of the cell. The muscles for the retraction of the animal are contained in the visceral cavity, and consist of two bundles of delicate thread-like chords (fig. 3. a 8 and 9.) ; the one set (a 8.) arising from the bottom of the cell to be inserted about the base of the stomach ; the other (a 9.) also arising from near the bottom of the cell, though ge- nerally at the opposite side from the former, and passing up free by the side of the pharynx to be inserted around the line of junction of this organ with the base of the tentacula. The muscles provided for the retraction of the operculum, or flexible portion of the cell, have their origin from the inner surface and near the top of the stiff part, and are inserted into the flexible portion, on which they act. (fig. 3. & 2 and 3.) They are most distinctly seen when the flexible operculum is completely drawn in, at which time the latter is folded up, so as to occupy the axis of the upper part of the cell, and to it the muscles are seen extending inwards from the opposite sides of the cell from which they have their origin. They consist of six flattened bundles of fibres having a tri radiate arrangement. The upper three sets ( b 2.) act upon the flexible part of the cell and are inserted into it. The lower three (b 3.) are smaller, and are for the purpose of retracting the bundle of setse by which it is crowned. It is at this point that the best opportunity is afforded for investigating the struc- ture of this form of muscle. It would appear as if muscular fibre were here reduced to its simplest condition. The filaments are totally disconnected, and are arranged the one above the other in a single series. They pass straight and parallel from their origin to their insertion, and have a uniform diameter throughout their course, ex- cept that each filament generally presents a small knot upon its centre, which is most apparent when it is in a state of contraction, at which time the whole filament also is obviously thicker than when relaxed. The filaments have a watery transparency and smooth surface, and under the highest powers of the microscope present neither an appearance of cross markings nor of a linear arrangement of globules. These muscles, though apparently attached to the inner walls of the cell, must yet have the membranous parietes of the body interposed between their insertions and these walls, if as I suppose the cell is completely lined by the integument. In the lower part the integument is only occasionally seen separate from the walls of the cell, but above it may be easily discerned in the expanded animal passing up to be inserted around the tentacular ring, and thus distinctly bounding this part of the body which is always free within the expanded operculum. It is probable, therefore, that the retractors of the operculum as well as those of the body are within the visceral cavity, and that the relation of the origins of both, with regard to the integument and cell is similar to that which exists in the attachment of the muscles, with refer- ence to the mantle and shell of bivalve Mollusca. This is easily understood if we suppose that the integument in this case, as I have ascertained it to be in another species, is attached to the operculum on a line with the base of the setse, which is the DR. A. FARRE ON THE STRUCTURE OF THE CILIOBRACHIATE POLYPI. 395 highest point upon which the opercular retractors act, and from which it is there carried up free to the tentacular ring. This being the mechanism by which the retraction of the animal within its cell is effected, I proceed to explain the mode of its operation. The tentacula from being expanded in the form of an inverted cone are brought together into a straight line and immediately begin to descend. Their descent is effected by the contraction of the muscle which passes from the base of the cell to the tentacular ring, (fig. 3. a 9.) whilst at the same time the stomach is drawn down by its retractor. (3. a 8.) The whole body, however, does not descend in a mass, but must be folded up in a somewhat complicated manner, in order that the cell may completely inclose it. For this purpose the oesophagus, surmounted by the tentacula, descends first, whilst the integument of the upper part of the body begins to be in- verted at the point where it has its insertion around the tentacular ring. As the de- scent of the tentacula proceeds, the inversion of the integument continues, forming a close sheath around them, (Plate XXI. fig. 12. c) until the extremities of the arms have descended to a level with the top of the unyielding portion of the cell. The animal is now completely drawn in, the stomach brought close to the bottom of the cell, and the oesophagus bent in the form of a letter S ; the tentacula generally lying straight in the axis of the cell encased in their tegumentary sheath, and so separated from the fluid in the general visceral cavity ; the centre of which they have the appearance of occupying, whilst they are in effect external to it. The animal being thus retracted, the next step of the process is to draw in the upper part of the cell after it. This process, however, always commences before the retraction of the body is completed, and by the time that the end of the arms are on a level with the base of the setae. (fig. 11.) These latter bodies are then immediately brought together in a bundle, and begin to descend apparently by the action of the lower of the two sets of oper- cular retractors already described. Their descent, like that of the tentacles, takes place exactly in the axis of the upper part of the cell, and is accompanied by an in- version around them of its flexible portion, similar to that of the integument of the body around the tentacula during their descent (fig. 10.). Whilst the lower set of muscles are drawing down the setae, the upper set complete the retraction of the flexible part, and the whole operculum is thus packed closely in the upper part of the cell, the end of which now presents a triangular indentation, corresponding with the triangular arrangement of the opercular retractors (fig. 3. b, and fig. 9.). In this position of the animal it is impossible to define the whole course of the in- tegument, but when the tentacles are drawn unusually low, (fig. 9.) that portion of it which forms their sheath may be readily seen passing up to the base of the setae, around which it appears to have an attachment, and to be then continued up the sides of the inverted operculum to the angle at the top of the cell, whence it probably again descends to line the sides of the cell. Thus the whole process of retraction may be easily accounted for, and the office of 3 F MDCCCXXXVII. 396 DR. A. FARRE ON THE STRUCTURE OF THE CILIOBRACHIATE POLYPI. each set of muscles satisfactorily explained; but the 'protrusion of the animal is effected by a totally different mechanism. Of course the different stages of protrusion occur in the inverse order of those of retraction. The bundle of setee (fig. 10. a) first makes its appearance rising out of the apex of the cell, and followed by the flexible portion (fig. 11. b) on which it is set. The tentacula next pass up between the setae and thrust them asunder, while the in- tegument of the animal is seen gradually rolling outwards from around the tentacles, (fig. 12. c .) These latter continue to emerge and the integument to be everted from around them, until the base of the tentacles has risen above the top of the expanded setae, when the act of protrusion is completed, the tentacula separate and expand, and the cilia commence vibrating*. During repeated observations of the various steps of the process, I had in vain searched for a set of muscles having an antagonist power to the former and lifting the animal out of its cell. But I could discover no structure of this kind ; and in- deed it is not easy to imagine how such a mechanism could act, since the upper flexible portion of the sheath could afford no fixed point of attachment for elevating muscles, whilst from the want of rigidity in the bod}", and the manner in which it is folded up in its cell, no muscles arising from a lower point could effect its expan- sion. After examining several species for an explanation of this phenomenon, I at length obtained a clue to it from one more favourable for examination than the rest. (Plate XXIV. fig. 3. a.) In this species the body is capable of protruding for some distance beyond the mouth of the cell, in which state its delicate membranous walls may be readily traced downwards on one side to nearly the bottom of the ceil, (Plate XXIV. fig. 3. a 3.) from the inner surface of which they are capable of being separated in about one third of its circumference and from top to bottom of the cell, but remaining appa- rently in immediate connexion with the other two thirds. This separation of a portion of the parietes of the body from the inner surface of the cell, I found invariably to accompany the protrusion of the animal ; and on ex- amining further, I discovered upon this part of the body two rows of delicate, short, transverse filaments, arranged at a little distance from, and parallel to, each other. {a b and d 3.) These fibres were distinctly seen to contract whenever the protrusion of the animal took place, and to become relaxed again upon its retiring into its cell ; the walls of the latter being so pellucid that the minutest alteration in the form of these muscles was readily seen. When contracted to their utmost, each filament was reduced to just half its original length, at the same time that its thickness was doubled, and the little knot upon its centre appeared also somewhat thickened. (Plate XXIV. fig. 4 and 5.) During their contraction, the unattached part of the pa- * Figs. 9, 10, 11, 12, represent the different stages of protrusion and retraction in the order in which they occur. DR. A. FARRE ON THE STRUCTURE OF THE C I LI OB RAC H I ATE POLYPI. 397 rietes upon which they were arranged was seen to recede from the inner surface of the cell, and to be drawn into longitudinal lines, especially at their points of origin and insertion. When the animal retired they returned to their former dimensions. These parietal muscles, which in structure exactly resemble the retractors, I have observed in every species of ciliated polype that has since come under my notice, and have ascertained its existence in Bowerbankia. (Plate XXI. fig. 13.) These transverse filaments then, acting together from top to bottom of the space upon which they are arranged, must necessarily tend by their contraction to diminish considerably the diameter of the visceral cavity, and will therefore exercise a pressure upon the fluid which it contains. The effect of this will be to elongate the body in the direction in which it is most free to move, and it might be supposed that this would satisfactorily account for the act of protrusion ; but it must be remembered that the contents of the cavity are folded up in a complicated manner, and the cell closed by its operculum, the whole of which parts have to be unfolded in regular order before the act of expansion is completed. I doubt, therefore, whether this simple apparatus could accomplish this act unassisted; but I believe it to be mate- rially aided by the cooperation of the alimentary canal, which undoubtedly has the power of straightening itself from the sigmoid flexure into which it is thrown when the animal is retracted. I am led to think this from having frequently observed the great extent of motion which the upper part, especially of the alimentary canal, is capable of exercising, independently of any action of the muscles attached to it; and from having also noticed occasionally that, during the rising of the tentacula, the unfolding of the integument from around them seemed rather to follow as the con- sequence of their advance, than as being the means of effecting it, which cannot well be explained, if we suppose the fluid of the body to be driven upwards by the contrac- tion of the parietal muscles with sufficient force of itself to expand the upper part of the body, and so to carry up the alimentary canal and to thrust out the arms. And this appears the more probable when we observe that even in the simple hydriform polypes, the advance and receding of the animal in its cell is entirely effected by the action of the parietes of the body, which are analogous to the alimentary canal in the present case ; the hydriform polypes possessing no distinct muscles to assist in these operations. To return then to Bowerbankia. Let us see how far these considerations will ap- ply to the explanation of the phenomenon in question. The animal being retracted, with the stomach resting upon the bottom of the cell, begins to erect itself by straight- ening the alimentary canal ; and the tentacula must be the parts first to rise. Before, however, these can protrude from the cell it is necessary that the flexible operculum which closes the mouth of it should be unfolded. As there does not appear to be any separate apparatus for this purpose, and as I have never observed it to occur in- dependently of the motions of the animal, it may be presumed that this is effected by the pressure from below when the animal endeavours to rise. 3 f 2 398 DR. A. FARRE ON THE STRUCTURE OF THE CILIOBRACHIATE POLYPI. Thus the tentacles rising first would press up the little bundle of setae (Plate XXI. fig. 10. a.), that lies immediately above them. The pressure continuing, the flexible part of the sheath (fig. 11. b.) would be next unfolded, and the whole would then be expanded by the passage of the several parts in succession through them. (fig. 12.) It is now that the parietal muscles come chiefly into play, and by keeping the tegu- ments tense during the alteration in the position and form of the body, prevent any collapsing of its parietes, which might entangle the operation of any of its parts, and which, for the want of this provision, would be likely to ensue from the pressure of the surrounding fluid when the animal rises from its cell ; especially as there does not appear to be that ready communication between the interspace then left in the cell and the surrounding element, by which the water might flow in to supply the vacuum left by the change in the form of the lower part of the body, during the protrusion of the animal. This circumstance I had occasion to prove by noticing the forcible in- dentation of the stiff horny cell itself, by the pressure of the surrounding fluid, which in some instances followed this act, as is represented in Lagenella repens (Plate XXIV. fig. 2. a.). Further, by the contraction of these muscles the body may be so much elongated as to carry the base of the arms to some distance above the margin of the cell, by which the freedom of their action is considerably increased, the stomach, being then lifted from the bottom of the cell, hanging suspended in the visceral cavity. It would appear then that the act of protrusion is effected by the combined operation of the parietal muscles and of the alimentary canal, which in fact forms the principal part of the substance of the animal, the parietes being purely membranous, and having little else to do than to retain the fluid in which the viscera float. It is interesting to compare these parietal muscles with similar parts in animals of another class. Having been frequently struck with the close analogy which the ge- neral characters of the animal under consideration presents with those of the class Rotifera, especially in the character of the retractor muscles, I was led to compare the parietal muscles also with the parts which, in Hydatina senta, for example, are usually considered and represented as the dorsal vessel with its lateral branches. (For it must be understood that the parietal muscles of which I am speaking have no resemblance to the circular fibres that surround the bodies of vermiform animals, and are intimately blended with their integument, but have a totally dif- ferent character, being simple short filaments, occupying a very small portion only of the circumference of the body, and being apparently connected with the parietes only by their extreme points of attachment). Having procured therefore some specimens of Hydatina, I was not much surprised to find that the parts in the two animals were identical ; the transverse lines of Hydatina being obviously parietal muscles, which whenever the body becomes elongated may be observed by their contraction to draw that side to which they are attached into longitudinal folds, and to be again elongated whenever the body is shortened by the contraction of the longitudinal muscles, to which the former are evidently the antagonists. In this case the alimentary canal DR, A. FARRE ON THE STRUCTURE OF THE CILIOBRACHIATE POLYPI. 399 being- straight and not folded on itself, and the body being unshackled by a dense co- vering, the parietal muscles alone are adequate to effect its expansion. Upon a review then of this description of the organization of .Bowerbankia, it must be admitted that the mechanical functions are executed with a degree of perfection, which in a being so exceedingly minute cannot fail to excite our surprise and admi- ration : not less interesting either is it to observe the more vital operations of this highly organized species. The little animal, when in full vigour, is seen projecting from its cell with the arms extended and the cilia in full operation, the upper part of the body being frequently turned from side to side over the edge of the cell, the extremity of which, from its peculiar flexibility, moves along with it. The particles, carried to the mouth in the vortex produced by the action of the cilia, after remaining a little while in the pharynx, are swallowed by a vigorous contraction of its parietes, and carried rapidly down the oesophagus and through the cardia to the gizzard, which expands to receive them. Here they are submitted to a sort of crushing operation, the parietes of the organ contracting firmly upon them, and the two dark bodies being brought into apposition. Their residence, however, in this cavity is only momentary, and they are immediately propelled into the true stomach below, where they become mixed up with its contents, which during digestion are always of a dark rich brown colour, being tinged by the secretion of its parietal follicles. The food appears to be retained for a considerable time in the stomach, and may be frequently seen to be regurgitated into the gizzard, whence, after having been again submitted to its operations, it is returned to the stomach. Here it is rolled about by the contraction of its parietes, and at its upper part is frequently submitted to a rotating motion. This rotation of particles is chiefly near the pyloric orifice, and a mass may be frequently seen projecting through the pylorus into the intestine, and rotating rapidly in the direction of the axis of the orifice. In an animal having a similar form of pylorus to this, but in which the parts were more transparent, I could distinctly see the cilia by which this rotation is effected surrounding the orifice. The granular matter, after rotating for some time at the pylorus (a provision for preventing its too rapid escape from the stomach), passes into the intestine, where it accumulates in little pellets, that distend the parietes of the tube ; and it is possible that it may be here still further acted upon by these parietes, which have a spotted appearance. By the contraction of the intestine the little pellets of excrementitious matter are carried rapidly upwards to the anal orifice, which is seen to open, and the little pellet to be tilted over its edge, when it is immediately whirled away from the sight in the current produced by the ciliated tentacles, and the orifice of the tube again contracts. With regard to the mode in which the animals are united together, I could not dis- cover that any connection existed between them beyond that which results from their cells being placed upon a common stock. In almost every case, however, I could 400 DR. A. FARRE ON THE STRUCTURE OF THE CILIOBRACHIATE POLYPI. see a filament (possibly a tube) passing down from the base of the stomach into the short neck that connects the cell with the main stem, but beyond this I could not trace it. It appeared to be distinct from the retractor muscles, by which it was sur- rounded. The stem itself appears to be nearly homogeneous throughout, and no mo- tion of particles was ever observed in its interior. Each cell is capable of a slight degree of flexion upon the main stem, but the means by which that is effected are not obvious. The only mode of reproduction that I had the opportunity of witnessing was that by a process of gemmation from the common stock, or creeping stem, from which the young animals in various stages of growth were seen sprouting (Plate XX. fig. 2.). The smallest gemmae appeared to be homogeneous in texture, forming little nodules on the parent stem. Those further advanced were seen to present something like a boundary line, indicating the thickness of the parietes of the future cell. Within this, in others, wTas a little dark mass, which in larger ones presented a rough outline of the form of the complete animal. Those about half grown had all the parts distinctly traced out ; the retractor muscles completely formed ; the tentacles short and clumsy; the walls of the alimentary canal thick, and its cavity clearly defined, as well as the dark spots in the gizzard (fig. 3. cl.). These were commonly seen in all stages of growth up to full maturity, grouped together on the same stem without any order, the stem terminating in a blunt growing end. As I shall have occasion to notice in another part of this paper the second mode of reproduction in this class, namely, that by locomotive ciliated gemmules, but which I did not observe in the present species, I defer for the present the consideration of this subject. I cannot, however, avoid referring here to an appearance which I have commonly observed, that seems to be in some way connected with it. It is that of one or more rounded or oval bodies, of a brown colour, lying apparently loose within the visceral cavity, and near the bottom of the cell (Plate XXL fig. 14 and 15.). From their dark colour they are generally very conspicuous, especially as they remain in the cells long after the animal has perished and disappeared from them. From this circumstance it might be imagined, that they resulted from decomposition, were they not also frequently seen in the living animal. Moreover they have a definite form and size, and when removed from the cell and carefully examined are found to con- sist of a delicate transparent membrane, inclosing a brown granular matter to which their colour is due. (fig. 16.) It is further remarkable that they are often seen as large in animals not even half matured as in the adults (compare figs. 14 and 15.). Besides these I have sometimes noticed other bodies more nearly spherical, and of a milk-white colour, which when pressed, broke up into minute granules. I have ob- served as many as three of the white and two of the brown bodies in the same animal, (fig. 14.) but the former are seldom seen. The brown bodies, however, are so ex- tremely common, that I have seldom had occasion to examine any species of this class without detecting them. I have not, however, been able to ascertain their use. DR. A. FARRE ON THE STRUCTURE OF THE CILIOBRACHIATE POLYPI. 401 They do not appear to answer any purpose in the economy of the animal ; and from their persistence after its death, they would seem to have the power of resisting1 those forces which cause the decomposition of the other parts. It is most probable that they are connected with the process of reproduction, but whether they may be viewed as ovaries or as immature ova, and what relation the white and brown bodies have to each other, are considerations that might be reserved for further opportunities of elucidation. I have never detected any motion in the granules of which they are composed. PLATE XXII. Vesicularia spinosa, Thompson, Zool. Research. Mem. V. pi. iii. Syn. Corallina confervoides, Ellis, Cor. pi. xi. N. 17. b. B.C.D. Sertularia sericea, Pall., El. Zooph. p. 114. No. 65. Sertularia spinosa , Linn., Gmel. p. 3855. No. 23. Valkeria spinosa , Flem. Brit. Anim. p. 551. Gen. lxx. 198. This species forms part of the subject of Mr. Thompson’s memoir, whose name for it I have adopted. In this memoir, which contains but a very rough sketch of the animal, he calls the part that I have described as a gizzard the stomach, which latter organ he mistook for an ovarium. It might be difficult to select two species differing more in external characters than do this and the previous one, yet in the structure of the animal hardly any essential points of distinction can be observed : it is one of the smallest and most delicate species on our coast. The main stem, which is zig-zag, (fig. 1.) sends from each angle two branches that divide dichotomously to their extremities, which in growing branches are rounded, but in others sharp and spiny ; a circumstance that did not escape the notice of Ellis. The vesicles are so minute that they can with difficulty be detected by the naked eye. The animal has but eight arms, (fig. 3.) which are short and stiff, and during expansion remain nearly motionless in the usual funnel- like form, but may be occasionally seen separated so far from each other as to stand out at nearly right angles from the body: they are ciliated, but not armed with spines. The alimentary canal presents the same character as that already described in Bowerbankia ; but allowing for the much smaller size of the animal, is proportion- ately shorter and stouter. The muscular apparatus consists of the gastric and tentacular retractors, the former (fig. 8. a.) arising from the bottom, the latter, (8. b.) a little above from the side of the cell; two rows of parietal muscles (fig. 8. c.), and two sets of operculum retractors (fig. 8. d.), in which respect it differs from the former species, where there are three double sets ; and the triangular indentation at the upper part of the closed cell is consequently wanting. The cell is also much broader in proportion to its length, having a more oval form. The operculum is finished by a row of setae. The connect- 402 DR. A. FARRE ON THE STRUCTURE OF THE CILIOBRACHIATE POLYPI. ing stem has a remarkably definite character (fig. 2.). Between every dichotomous division is a joint bearing three cells, which, when they drop off leave a circular foramen. The cells are strictly unilateral upon the stem, and diminish in size very regularly towards the growing extremity ; the last few being mere buds from its surface. Within the stem may be seen a number of transparent, circular bodies of a tolerably uniform size, that appear to be attached to the inner surface. They very much resemble in appearance the granules which may be seen through the cell attached to the membranous parietes of the animal itself. These latter are smaller than those in the stem, and more scattered. I have not ascertained the use of either. Ellis was, I believe, the first to notice in this species what appears to be a direct medium of communication between the animals themselves. It consists of a thread of a darker substance than the rest of the stem, running within its upper surface im- mediately below the base of the cells. Ellis states* that the slightest movements of the animals were communicated to this substance, an observation that I have not been able to confirm ; but my specimens were not very lively. The point is one of interest and worthy of further investigation. PLATE XXIII. Valheria cuscuta, Flem., Brit. Anim. p. 550. gen. Ixx. 196. Syn. Corallina cuscutce forma, Ellis, Corall. N. 26. pi. xiv. c. C. Sertularia cuscuta, Linn., Gmel. p. 3852. No. 18. and Muller, Zool. Dan. 3S p. 62. t. 117- f. 1—3. Cuscutaria cuscuta, Blainv. Diet, des Scien. Nat. p. 461. Vesicularia cuscuta, Thomp. Zool. Research. N. IV. pi. ii. 1. This is the most minute species that I have met with. Its creeping stems are found closely adherent to the filamentous ramifications of a species of Ceramium, on which it grows parasitic, with much of the habit of Dodder, whence its trivial name (fig. 1. and 2.). It has been placed in the same genus with the species last described, but differs from it, and also from Bowerbankia, in the entire absence of the manducatory organ; a difference which it is of great importance to observe with reference to a natural ar- rangement of the class'^. The ciliated tentacles are eight in number, slender, and often widely spread, ex- hibiting a good view of the oral aperture (fig. 4. a.). The alimentary canal is here of some length, and acquires a considerable sigmoid flexure when the animal is at rest (fig. 5.). The intestine near its termination pos- sesses a decided rectal enlargement, which is very distinct even when empty (fig. 5. e.). * Essai sur l’Hist. Nat. des Corall. p. 36. f I have for this reason removed it from Vesicularia, and adopted the name previously given to it by Dr. Fleming. DR. A. FARRE ON THE STRUCTURE OF THE CILIOBRACHIATE POLYPI. 403 There appears to be but one set of parietal muscles in this instance. The retractors of the body resemble those of Bowerbankia, as do also those of the operculum in their division into an upper and a lower set, but there appear to be only two instead of three of each, as in Bowerbankia (fig-. 4. b.). The granules which adhere to the parietes are very distinct in this species, and re- main attached to the inner walls of the cell, after the rest of the animal has disap- peared (tig. 4. c.), together with the brown bodies which I have conjectured to be ovaries or ova. I have not generally observed more than one of these bodies in each animal of this species. A very remarkable agitation of particles, which was frequently observed in the vis- ceral cavity, and very closely resembled the irregular vibration of cilia, was found, by the aid of a very high power, to be caused by a multitude of minute cercarice (fig. 5.) swimming about with the greatest activity in the fluid with which that cavity is filled. When this cavity was laid open by a needle they escaped and swam away by the ser- pentine motion of their bodies. They consisted simply of a long slender filament, with a rounded extremity, by which they occasionally fixed themselves (fig. 5 • g.). Similar parasites were not unfrequently observed in other species. The cell is terminated by the usual row of setae (fig. 5 and fig. 6.). Froi'n the quantity of earthy material combined with its horny texture, it is rendered so opake as to present great difficulty in the examination of the contained parts. This cha- racter, which pervades the stem also, renders these parts exceedingly tough and strong; and notwithstanding its extreme fineness the stem will bear the exertion of a con- siderable degree of force without breaking. When these parts are pressed by the dissecting needle they yield a grating sound. The arrangement of the cells with regard to the stem is intermediate in regularity between that of the two former species. They are generally gathered in clusters which surround the stem (fig. 3. a.) ; the cluster nearest to the growing extremity having its ceils gradually diminishing in size, and more obviously springing from opposite sides of the base of support, the long spiny end of which often projects in a remarkable manner beyond the extremity of the branch upon which it creeps. The stem is often seen divided into joints at irregular distances,- and the cells are sometimes set on short branches springing from them (fig. 3. b.). PLATE XXIV. Lagenella repens , Mihi. Fig. 1. and 2. Parasitic, with a creeping stem, on Sertularia and on Halodactylus diaplianus. Not very common. This species has twelve ciliated arms (fig. 3. a), not spiny. The alimeutary canal is short and stout, and whilst the animal is expanded remains high up in the body. During retraction the stomach is never brought down to the bottom of the cell, but 3 G MDCCCXXXVII. 404 DR. A. FARRE ON THE STRUCTURE OF THE Cl LI OB RAC HI ATE POLYPI. remains suspended from the upper part of it by the intestine, which appears to have some attachment at this point. The upper part of the tube, however, is generally brought down lower than the stomach, in order that the tentacles may be completely drawn in (fig. 3. c.). By this suspension of the stomach from the upper part of the cell a fixed point is obtained, from which the retracted flexed portion of the tube may erect itself with the same effect as if the stomach were in contact with the bottom of the cell. This is a point which it would be important to observe in generic distinc- tions ; but here, as with many other points in this species, my observations were not carried to the extent that they have been in others, as this was one of the specimens with which my investigations were commenced, and I have never since had an oppor- tunity of confirming them. This is the more to be regretted, as from the complete isolation of the cells, and the extreme transparency of their parietes, a clearer view of their contents is obtained than in any species that I have subsequently met with. The spots upon the pharynx, and their absence in the triangular ciliated space, were remarkably distinct (fig. 3. a 1.), as was also the difference between the dark brown colour of the hepatic follicles in the replenished stomachs, and their pale and almost inconspicuous character in the empty ones. (Compare a and h. fig. 3.) The position of the cardia was not ascertained. When the body was turned so that the pylorus was presented to view, and this happened to be empty, a row of cilia were distinctly seen surrounding it. The vibration of these cilia, as well as of others which were observed in the stomach, appeared to be entirely under the control of the animal. Their action was frequently observed to be suddenly suspended, when the rotation of particles ceased also, and when it recommenced the motion of particles was renewed. This rotation was often so rapid at the pylorus that I should think from one to two hundred revolutions must have been performed in the minute. When very small animalcules were introduced into the bulging pharynx, several convulsive efforts were sometimes made before they could be swallowed ; during these the animalcules not unfrequently escaped again by the mouth, but were intercepted by one of the ten- tacula being bent forward and striking the animalcule as it rose with a sharp blow that drove it back again into the pharynx. The animalcules did not immediately perish in the stomach, but continued their motions for some time after being intro- duced into it. The gastric and tentacular retractors are particularly distinct, and have the usual origins and insertions (fig. 3. d 1 and 2.). The double row of parietal muscles (fig. 3. d 3.) have been already described in the notes on the species first quoted. There ap- pears to be but one set of retractors of the operculum (fig. 3. d 4.), which is generally drawn towards the side of the cell from which they arise, leaving a slight indentation in the top of the latter when retracted (fig. 3. c.). The granules on the parietes are less numerous than in most instances, but very conspicuous. The cells have an oblong form, and are connected to their narrow creeping stem by a short peduncle. The opercular portion terminates in a notched margin, and is DR. A. FARRE ON THE STRUCTURE OF THE CILIOBRACHIATE POLYPI. 405 very short (fig. 3. a 4.). (It is possible that this notched margin may be formed by the extremities of short and broad setae, but this was not determined.) The cells spring from the sides and upper surface of the stem, and turn upwards as in Bnwer- bankia. They are set at some distance apart. The gemmae exhibit the same process of growth as in other cases, and are scattered irregularly amongst the larger cells (fig. 3.). PLATE XXV. and XXVI. Halodactylus diaphanus, Mihi#. Syn. Alcyonium seu Fucus nodosus et spongiosus, Ellis, Cor., p. 102. pi. xxxii. fig. d. D. Alcyonium gelatinosum , Linn., Gmel., p. 3814. No. 11. Lamx. Polyp, flex., p. 350. No. 495. Mull. Zool. Dan. iv. p. 30. t. cxlvii. f. 1 — 4. Flem. Brit. Anim. p. 517- gen. xl. 86. Alcyonidium diaplianum , Lamx. Gen. Thalass. p. 7L t. 7- f. 4. Hooker, Flora Scotica, part II. p. 75* London Encyc. of Plants, 1829, p. 928. Ulva diaphana, Hudson, Flor. Angl., vol. iii. p. 570. Sowerb. Engl. Bot. t. 263. Extremely common on the Sheppy coast, especially after a gale, when it is cast up in immense quantities, and is found attached to loose stones and shells, in the form of soft, flexible, finger-like processes of very irregular figure, being rounded and smooth upon the surface, or flattened, nodulated and branched, sometimes attaining the length of two or three feet, but generally about six inches long. The animals are, however, so small that such specimens must contain many millions of them. When a portion of this is placed in a trough of sea-water, the little animals are seen quickly to emerge in such numbers as to cover its surface with a coating as it were of the finest down ; and they are so closely set that there seems to be hardly room for their several operations (fig. 1.). In this state it is scarcely possible to make any observa- tions upon them, but when a few only are projecting they become from their extreme delicacy and transparency peculiarly favourable subjects for examination. On this account, and also from the length of time that they may be kept in vigour, I have been enabled to prosecute the inquiry further than other specimens enabled me to do. Plate XXVI. fig. 7- The tentacula are sixteen in number, (occasionally fifteen)! fully two-thirds the length of the body of the animal, and extremely slender and * aXs et SaurvX os. The confusion and doubt which have so long pervaded the very ill-defined genera Alcyo- nium and Alcyonidium appear likely to be dispelled only by beginning de novo, and adopting a new name in conjunction with characters sufficiently definite to preclude all probability of further error. I have therefore renamed the present species as indicative of a new genus, with which other species will probably he found, upon a minute examination of their intimate structure, to possess congeneric affinities. f Fleming, Lamouroux and others appear to be in error in stating them to be twelve. 3 g 2 406 DR. A. FARRE ON THE STRUCTURE OF THE CILIOBRACHI ATE POLYPI. flexible. When expanded they are frequently seen to roll up closely upon themselves, (fig. 18.) even down to their base, the revolution taking place either inwardly or outwardly, and in one or more arms at the same time. Their full expansion affords a more perfect campanulate form than is usually met with in this class, each of the arms having a slight curve outwards towards its extremity, which gives to the whole a very elegant appearance. It is remarkable that in some specimens the arms are much shorter on one side of the body than on the other. In many positions this is not very striking, as it might be attributed to an appearance of fore-shortening of that side which happens to be turned towards the observer, (fig. 17.) but when viewed laterally this character is very obvious (fig. 16.). The arms when viewed with an amplifying power of 200 linear are seen to be tubular throughout, (fig. 19. a.), and to have an aperture at each extremity. The aperture at the apex is extremely small, and in a lateral view sometimes appears like a slight notch at the extremity of the arm. The apertures at the base are seen more plainly, and are situated in the centre of the tentacular ring, one corresponding with the base of each arm (fig. 8.). I have also sometimes observed what would seem to be a fine canal, running round in the sub- stance of the ring, and apparently uniting the tentacular canals (fig. 10.). It would be exceedingly interesting to ascertain with what parts these tentacular canals com- municate. As the tentacles appear to be respiratory as well as prehensile organs, it is most probable that the canals by which they are permeated are for the purpose of allowing a circulation of fluid through them; but from the minuteness of the parts and the agitation of the surrounding medium by the rapid action of their cilia, it would be a matter of great nicety to detect such currents though they should exist. The action of the tentacular cilia appears entirely under the control of the animal, and they are sometimes seen completely at rest. If, however, a portion of one of the arms be cut off, the action of the cilia continues as vigorous as before, and the isolated part is carried about in the field of the microscope. When the animal is dead, these cilia are seen to be longer and considerably more numerous than they appeared to be when in action (fig. 19. a.). As the parts gradually perish the cilia disappear, and the surface of the arms becomes covered with a granular matter and the part shrinks to a mere thread (fig. 19. h and c.). The ring upon which the tentacles are set is well marked, and terminates on its inner circumference by a sharp edge projecting to form the mouth of the pharynx. It is probable that this tentacular ring never contracts except to bring the base of the tentacles together. But whilst it remains fixed so as not to alter the arrangement of the arms, the closing of the mouth of the pharynx is effected by the constriction of the parts immediately below it, which there appear as if they had been bound round with a ligature (fig. 8. d.). The pharynx (figs. 7? 8 and 9.) is very short in this species, and its parietes are covered by the peculiar spots already noticed, except in the triangular space at the upper part (fig. 9. c.) which is entirely free from them, and where a vibration of DR. A. FARRE ON THE STRUCTURE OF THE CILIOBRACHI ATE POLYPI. 40/ cilia may be occasionally detected. On the opposite side, generally, of the pharynx, may be seen a line (fig's. 8 and 9. a.) running down to the cardia, and if this part be observed for a short time it will be seen that the pharynx is repeatedly distended, as by a sudden act of insufflation, and that whenever this distention takes place the part bounded by the line becomes expanded but quickly returns to its former position. It is probable that there is here a muscular apparatus by which these sudden expan- sions of the pharynx are effected. When at rest this part has much the appearance of a tube, which is marked by rough cross lines, and wants the spotted character of the surrounding parts (fig. 9.). This sudden expansion of the parietes of the pharynx, which takes place at irre- gular intervals, appears to be connected with the act of respiration as well as of nu- trition; for not only are the particles of food thus admitted more freely into the sac, but the water is more readily renewed and brought more effectually into contact with its inner surface. With a view of determining to what extent the flow of water into the pharynx took place, some particles of carmine were diffused through the fluid in which the animals were placed. As soon as the cilia commenced vibrating, the particles of carmine were put into rapid motion, (fig. 7-) being carried in a stream down the inner surface of each arm, the greater part passing out again between their bases ; while of the remainder part turned upwards again and issued from the centre of the expanded arms, (a course best seen when the arms were turned forward) and a few were carried through the mouth into the pharynx, where they were submitted to a rota- tory motion by the action of the cilia lining its upper part ; and after remaining there a short time some were swallowed, while the rest escaped at the mouth, and their place was supplied by others. From this experiment it did not appear that the flow of fluid into the pharynx was so free as might be expected, seeing that the mouth is almost constantly open ; for except during the act of expansion, by which the sac is suddenly filled with water, the parietes are so nearly in contact as to obliterate a large portion of its cavity: at every expansion, however, the greater part of the water must be renewed. The size of the particles which the animal swallows appears to be regulated con- jointly by the mouth and tentacula. The aperture within the tentacular ring, which forms the mouth of the pharynx, is not capable of distention like the mouth of Hydra ; for if this part were to be engaged in swallowing large prey, the whole tentacular apparatus would be thrown into disorder, and the regular flow of fluid to the pharynx interrupted. Whilst, therefore, the diameter of the mouth prevents the admission of the larger particles, the size of the smaller ones will be regulated by the spaces be- tween the tentacula, which, like a sieve, of a degree of fineness proportioned to the number of the arms and the consequent width of their intermediate spaces, would allow all the finest particles to drain away, and retain in their area only those of an intermediate size. These readily flowing into the pharynx become subject to a selec- 408 DR. A. FARIIE ON THE STRUCTURE OF THE C1LIOBRACHIATE POLYPI. tion of a less mechanical nature, in accordance with which some are swallowed and others rejected. In the act of swallowing- the mouth is closed by the constriction below the tentacular ring-, and the sides of the pharynx being- brought into apposition, principally by the action of the part already alluded to, the particles are forced through the cardia, which projects into the pharynx with a nipple-like prominence (fig-. 8. A). As all below this point appears to be concerned more or less in the office of diges- tion, the stomach may be considered as commencing here, though in form it might rather resemble an oesophagus. The hepatic follicles, however, reach nearly as high as the cardia (fig. 7- «■)• If then the cardia be taken as the line of demarkation be- tween the pharynx or oesophagus and the stomach, without regard to its variable po- sition in different species, then it will be found that in some the pharynx is short and the stomach very long, as in the present instance, and in Valheria cuscuta ; whereas in Bowerbankia, where the cardia is low down, the reverse obtains, and the pharynx is of great length, while the stomach is comparatively short. Those who would follow out the analogy which undoubtedly exists between these, animals and those of the class Tunicata, and would compare the pharynx in the pre- sent case to the respiratory sac in Ascidia, might contend that the upper aperture of the pharynx being analogous to the entrance to the respiratory sac in Ascidia, then the lower aperture should be called the mouth, as being placed at the bottom of the sac. As, however, the pharynx is here certainly an organ for the reception and deglutition of food, and only probably concerned in respiration ; it would be more consistent to use the names as I have applied them ; the upper and lower apertures being respec- tively mouth and cardia, while the intermediate space may be designated from its probably double function, respiratory pharynx. The distinction, if contended for, would be at best but one of names and could not improve the analogy. The stomach is not furnished with a gizzard in this species. The intestine forms a considerable elbow at its origin, and is short and wide, terminating- not as in other cases near the tentacular ring, but about midway up the body, at a point opposite the base of the setae (fig. 7- «•)* A very singular organ (figs. 16, 17 and 18. b.) was frequently observed consisting of a little flask-shaped body situated between the base of two of the arms, and attached to the tentacular ring by a short peduncle. The cavity in its interior is lined with cilia which vibrate downwards towards the outer, and upwards towards the inner side; it has an arrow neck and a wide mouth, around which a row of delicate cilia are constantly playing. No flow of fluids could gver be detected through it, nor did the use of carmine assist in showingwith what parts the cavity in its interior might com- municate. From the circumstance that it is more frequently absent than present, it cannot be an organ of vital importance to the animal ; and it is too intimately blended with the sides of the tentacula and too constant in its position to be regarded as a parasite. Does it indicate a difference of sex ? DR. A. FARRE ON THE STRUCTURE OF THE CILIOERACHIATE POLYPI. 409 The peculiar fleshy character which caused the name gelatinosum to be applied to this species arises from the mode in which the cells are united together. Their arrangement is best seen by making a thin transverse slice of the main substance and examining it with a low power (Plate XXV. fig. 3.). The cells are then found to be arranged parallel with one another and having their sides united together so as to form a compact ring, of which the bases constitute the inner and the apices the outer circumference. The centre of the cylinder, of which this is a section, is occupied by a light cellular tissue and a clear fluid, probably water. In such a section similar brown bodies to those already described are seen in great numbers, and not confined to the cells, but dispersed through the whole substance. The arrangement of the cells being thus shown, a more accurate view of their structure is obtained by exami- ning a thin section made parallel with the surface (fig. 4.). In this view their ends only are seen having an hexagonal form, from their pressure upon each other, but in each compartment the animal may be discerned with all its parts. Sometimes, how- ever, the cells, instead of being arranged parallel to one another, lie so obliquely, that their sides instead of their apices form the outer surface ; an arrangement which bears a close resemblance to that of the cells of Flustra (fig. 5.). But in order to witness the different stages of protrusion and retraction a portion of the mass must be viewed edgewise (Plate XXV. fig. 2. and Plate XXVI. fig. 7-)* In which position, although the lower part of the cell and animal is generally concealed from view, all the most interesting parts may be observed as they rise in succession above the sur- face. The stages of protrusion and retraction occur in the same order and with nearly the same phenomena as in Bowerbankia. (See the series from fig. 11 to 16. Plate XXVI.) The arms, however, instead of rising straight are often seen bent upon themselves, a provision that appears to be necessary, on account of the great length of some of them, in order that they may be completely inclosed in the cell. The upper portion of the cell, from its superior transparency and flexibility, ap- pears to contain little, if any, earthy matter. The setse (fig. 7- « andc?.) are very stout and short, broad at their base, and few in number. The body projects to an unusual distance beyond the mouth of the cell (fig. 7- «.), and its delicate parietes may be seen separate from the whole circumference of the cell, except where they are attached to the edge of the operculum at the point whence the setee arise. Cercarise were seen in the bodies of these animals which did not differ in any re- spect from those of Valkeria, and occupied a similar position. On one occasion these were observed drifting rapidly to the upper part of the visceral cavity, and shortly after issued from the centre of the tentacula ; but as the animal had in the mean time half withdrawn itself, I lost the opportunity of tracing their course. It would appear from this that there is some external communication with the cavity of the body. The process of reproduction by gemmation (in this case by the growth of young animals and cells amongst the mature ones) may be seen in every specimen (Plate XXV. fig. 4.). The smaller cells are triangular, and the animal forms a mere spot in its 410 DR. A. FARRE ON THE STRUCTURE OF THE CILIOBRACHIATE POLYPI. centre. As they grow they thrust aside the surrounding cells, and the number of their sides increases until they acquire the irregular hexagonal form of the adult. In the oblique position of the cells (in which they look like a new growth encrusting the old mass like a Flustra ) the young cells are less angular, and arranged more regu- larly at the spreading edge (fig. 5.). This species afforded an opportunity of examining also the reproductive gemmules. These are readily seen in spring as minute whitish points just below the surface of the mass (fig. 3. a a.). Sometimes they are of a darker colour, and exceedingly nu- merous, appearing to occupy almost the whole substance. If one of these points he carefully turned out with a needle it is found to consist of a transparent sac (fig. 20. a.), in which are contained generally from four to six of the gemmules, which, as soon as the sac is torn, escape and swim about with the greatest activity, affording a most interesting subject for microscopic investigation. When viewed with a power of forty, linear measure, they are seen to be of an oval or rounded form (fig. 20. b and c.), convex above, and nearly plane below, and fringed at the margin with a single row of cilia, which appear to vibrate in succession round the whole circumference. Under an amplification of 120 they assume a different aspect (fig. 21. and 22.), and their minute structure is clearly discerned. Viewed as opake objects, both the body and cilia have a silvery whiteness, but by transmitted light the former appears of a dark brown, and the cilia of a golden yellow colour. Upon the most convex part of the body, which is not generally in the centre, but leaning to one side, are set from three to five prominent transparent bosses surrounded by a circle ; and other circles are seen extending to the base of the body, the extreme margin of which is bounded by a row of prominent tubercles. These marginal tubercles are from thirty to forty in number, and from the circumstance of the cilia arising from them, it is probable that they are for the purpose of governing their motions, and therefore analogous to the muscular lobes of Hydatlna senta. No structure, how- ever, could be detected in these, nor in any other part of the body beyond a mere granular parenchyma. Fig. 22. Under this power the whole character of the ciliary motion is changed, and it is seen that what before appeared to be a single cilium is in fact a wave of cilia, and that their motion, instead of being in the direction of the circumference of the disc, is at right angles to this. The ciliary phenomena are the most readily ob- served when the gemmule is nearly at rest, or has become languid ; it then lies either with the convex or the plane side uppermost, and with the cilia, which are of great length, doubled in the middle upon themselves (fig. 21.), so that their extremities are brought back nearly to touch the margin of the disc from which they arise. The whole fringe of cilia is then suddenly unfolded, and after waving up and down with a fanning motion they are either again folded up towards the under surface of the body, or they commence their peculiar action. As the cilia have the appearance of moving in waves round the disc (fig. 22.), each wave may be thus analysed. From a DR. A. FARRE ON THE STRUCTURE OF THE C1LIOBRACHIATE POLYPI. 411 dozen to twenty cilia are concerned in the production of each apparent wave, the highest point of which is formed by a cilium extended to its full length, and the lowest point between every two waves by one folded down completely upon itself, the inter- vening space being completed by others in every degree of extension, so as to present something of the outline of a cone. (And it is remarkable that one of these corre- sponds very nearly in breadth with one of the supposed muscular lobes.) As, how- ever, the persistence of each cilium in any one of these positions is only of the shortest possible duration, and each takes up in regular succession the action of the adjoining one, so that cilium, which by being completely folded up formed the lowest point be- tween any two waves, now in its turn by its complete extension forms the highest point of a wave; and thus while the cilia are alternately bending and unbending them- selves, each in regular succession after the other, th e waves only travel onward, Avhilst the cilia never change their position in this direction, having in fact no lateral motion. When the waves travel very rapidly they appear smooth on one side and fringed on the other (fig. 23.). The whole of the ciliary motions are so evidently under the entire control of the animal as to leave not the slightest doubt in the mind of the observer as to this point. The whole fringe of cilia may be instantly set in motion, and as instantaneously stopped, and their action regulated to every degree of rapidity. Sometimes one or two only of the waves are seen continuing their action whilst the remainder are at rest, or isolated cilia may be observed slowly bending and unbending themselves, or projecting entirely at rest (fig. 21.). The body is generally somewhat pointed towards one extremity of the oval, and at this part may be observed a bundle of cilia, longer than the rest, and moving very rapidly (fig. 21. a.). Their vibrations were in several instances counted very evenly at 230 times in the minute, continuing in action whilst all the others were folded up. These may be respiratory, whilst the others are chiefly locomotive. There can be little doubt that this explanation of the action of the cilia in the gemmules is applicable also to those of the tentacula of the adult animal, and not only in this species but throughout the class generally ; for I have already observed that the tentacular cilia are infinitely more numerous when at rest than they appear to be in action : and I have also noticed, when their motions become languid, that here also they vibrate, not in the direction of the plane of the arms, but at right angles to it, and with the same hook-like form as in the gemmules. In this way the apparent travelling of the cilia up one side of the arm and down the other, as the eye is seduced to follow the waves which they seem to produce, is at once ex- plained. It would be impossible to explain the variety of motions which the gemmules are capable of executing, were it not obvious how complete is their control over the ac- tion of the cilia, which are their sole locomotive organs. They generally swim with the convex part forwards, and with the greatest rapidity. Sometimes they simply rotate upon their axis, or they tumble over and over ; or selecting a fixed point they whirl round it in rapid circles, carrying every loose particle after them. Others creep mdcccxxxvii. 3 H 412 DR. A. FARRE ON THE STRUCTURE OF THE CILIOBRACHIATE POLYPI. along the bottom of the watch-glass upon one end and with a waddling gait; but generally after a few hours all motion ceases, and they are found to have attached themselves to the surface of the glass. At the expiration of forty-eight hours the rudiments of a cell were observed extending beyond the margin of the body (fig. 24.); but at this stage the animals invariably perished, and during repeated observations I had no opportunity of witnessing their further metamorphosis. At this stage the cilia had disappeared, and the muscular lobes were no longer apparent. None of these gemmules were spontaneously evolved, and their death appeared to be owing to their premature extraction. The parenchyma of the gemmules has a contractile power, somewhat like that of Hydra, but less in degree, by which the form of the body is occasionally altered. If a portion of the margin with the cilia attached be torn off. the cilia continue to vibrate, as when a portion of one of the tentacles has been so isolated. PLATE XXVII. fig. 1—5. Memhranipora pilosa , Blainv. Syn. Eschar a Millepora , Ellis, Corall. pi. xxxi. f. a. A. Flustra pilosa , Linn., Gmel., p. 3827* No. 3. Blainv., Diet, des Scien. Nat., Art. Zooph., p. 415. Flem., Brit. Anim., p. 53 7. Gen. Ivi. 147- Flustra dentata, Linn., Gmel., p. 3828. No. 11. Ellis, Corall. pi. xxix. d. Blainv., Diet, des Sc. Nat., p. 414. This evidently belongs to the genus Memhranipora of Blainville #, though not in- cluded in it by him. It unites Flustra pilosa and dentata ; the only difference be- tween which is in the length of the anterior spine of the ceil, a character which varies in every degree even in the same specimen. Fig. 1. The animal in many respects very closely resembles Halodactylus dia- phanus, but its form is far less elegant. The arms are twelve (rarely eleven) in number, ciliated and furnished with long spines. They are very long in proportion to the body, but thick and rather clumsy, and during expansion are frequently curled inwards at their extremities. The base of the tentacles appears to be surrounded by a delicate band, which is placed on their outer side as if for the purpose of bringing them together, and imme- diately within which they unite to form the tentacular ring (fig. 2.). The appearance of a circumferential vessel in the substance of the ring, and the tentacular canals were observed here as in Halodactylus. The pharynx also in every respect confirmed the observations upon that species, especially in its mode of expansion, and in the position of the dark line, the triangular space, &c. The flask-shaped body was here also occasionally observed, but without affording any additional information. It was much larger in proportion to the length * Diet, des Sc. Nat. Art. Zooph., p. 411, DR. A. FARRE ON THE STRUCTURE OF THE CILIOBRACHIATE POLYPI. 413 of the arms, and was sometimes seen to be much distended and to alter its form oc- casionally (fig-. 3 and 4.). The cardia is placed about midway between the mouth and the base of the stomach, the whole canal being very short. The intestine terminates in the membranous pa- rietes at a little distance below the ring (fig. 1. a.). The separation of the parietes from the cell when the animal emerges is very distinct. The lateral aperture in the cell is filled by the flexible membranous portion, which does not terminate here by setae, but has a plain margin (fig. 1. b.), forming a close ring round the protruding animal. The cells are met with either isolated or aggregated; in the latter case the growth of the young cells is seen in advance of the older ones, and they appear to spring from the upper and back part of the cells immediately below them (fig. 1. c.). The cells are often seen connected by cylindrical stems which do not appear to belong to them. PLATE XXVII. fig. 6—9. • Notamia loriculata, Flem., Brit. Anim., p. 541. Gen. lx. 158. Syn. Corallina cellifera mollis ramosissima, Ellts, Corall., p. 55. pi. xxi. n. 7- b. B. Sertularia loriculata, Linn., Gmel., p. 3858. No. 31. Cellularia loriculata, Pall., Zooph., p. 64. No. 22. Crisia loriculata, Lamx., Polyp, flex., p. 140. No. 250. Gemicellaria loriculata, Blainv., Diet, des Sc. Nat., Art. Zooph., p. 425. Loricaria Europcea, Lamx., Expos, methodique des genres de l’ordre des Polypiers, p. 7* * Fig. 6 and 7. This is a ramified species very common on the Sheppy coast. The arms are ten in number, ciliated and flexible (fig. 9.). The alimentary canal presents the usual details (fig. 8. a.) The pylorus is very distinct, and there is a considerable rectal enlargement. The pharynx is spotted. The gizzard wanting. Fig. 7. The branches, which are given off generally form opposite points of the main stem, are formed like it of a succession of cells, placed back to back in pairs, the last two or three pairs gradually diminishing in size, with a corresponding degree of development of the contained animals ; the terminal pair is generally very small, and apparently homogeneous in texture, and without a trace of its future animal inhabitant (fig. 8. c.). Fig. 8 and 9. From this position of the cells the animals cannot emerge from their extremities, but protrude laterally by the oval aperture in the upper part and side of the cell. This is closed, as in Membranipora, by a more flexible portion than that which forms the rest of the cell, (which is only a modified form of the flexible oper- culum in the foregoing species,) leaving a horse-shoe aperture for the passage of the tentacula and upper part of the body (fig. 9. a.). Here the process of gemmation occurs 3 h 2 414 DR. A. FARRE ON THE STRUCTURE OF THE CILIOBRACHIATE POLYPI. in vei-y regular order, the smaller cells as in Membranipora, growing from the upper and inner sides of the larger ones immediately below them. It is evident that in the construction of the cell, Membranipora and Notamia are closely allied, and notwithstanding the encrusting character of the former species, and the ramified habit of the latter, it would be easy in imagination to convert the one into the other by supposing two lines of growing cells, such as are often seen in M. pilosa, to be attached back to back to each other : from these similar branches arising the encrusting species would be converted into the ramifying one. And the further passage of this to the arrangement in Flustra is accomplished simply by the union of a parallel series of such branches. Such then are the principal facts that have offered themselves to my notice during the investigation of the above described species. They afford evidence of the ex- istence of a very decided type of structure, and one which presents a remarkable uniformity of character, notwithstanding that it was observed in genera differing con- siderably in less important particulars. To what extent, however, this prevails, and how far it may be modified in other genera, are considerations which must be re- served for a more extended inquiry to determine. Among the points requiring further elucidation, one of the most important is the condition of the nervous system. No trace of either nerves or ganglia could be detected ; yet the attributes of a nervous system were so clearly exhibited as to leave no doubt but that this must exist, and probably in some degree of perfection. Not only was the delicacy of their sense of touch very strongly marked, but the operations also consequent upon the enjoyment of such a sense were sometimes singularly striking. This is seen in the instant re- tiring of the animal on the slightest alarm, and the caution which it sometimes shows before emerging again from its cell* ; in the obvious selection of its food ; and in the pertinacity with which it refuses to expose itself to water that has become in the least degree deteriorated. The respiratory system, again, being so intimately connected with the digestive apparatus, it becomes difficult to determine, from witnessing the combined operations of the parts, in what degree they contribute to the performance of each function re- spectively. The peculiar action by which the pharynx becomes so frequently dis- tended, and the constancy of the currents produced by the tentacular cilia, (appa- rently far beyond what would be necessary to afford a sufficient supply of food,) * On several occasions I observed in Halodactylus one or more of the tentacles protruded and turned over the side of the cell before the animal ventured out again, after having been alarmed by the sudden contact of some vibriones that abounded in the water used, as if to ascertain the presence or absence of the intruder (plate xxvi. f. 7. b.) ; a position of the arms which is also frequently assumed in this species in the act of retiring. So delicate indeed is the sense of touch, that the creeping of a very small animalcule over the top of one of the closed cells was followed instantly by a shrinking of the soft parts beneath. DR. A. FARRE ON THE STRUCTURE OF THE CILIOBRACHIATE POLYPI. 415 together with the circumstance that the particles so brought within its reach seem frequently rather a source of annoyance than of advantage to the animal, are points which would encourage the belief that these parts have a considerable share in the process of respiration ; but until the existence of a circulatory system and its course shall have been determined, the consideration of this as a respiratory apparatus must yet remain conjectural, though supported by very strong analogies. On the other hand, its use in ensuring a supply of food to the animal cannot be questioned. The structure and growth of the cells, and their connecting medium, offer many interesting points for consideration. In the ramified and creeping species the cells are connected by a cylindrical stem, which appears nearly homogeneous throughout, and does not present that obvious distinction between hard and soft parts that is ob- served in the stems of Sertularia. If, however, this stem be cut across, especially when decomposition has commenced, a granular matter flows out, leaving the delicate corneous sheath nearly empty. This corneous case of the stem is easily seen to be continuous with the cells that arise from it, but the internal substance cannot be di- stinctly traced to the animals as in Sertularia. It is probable, however, that it passes gradually into the parietes of the body by which the cells are lined. With the facts before us of the progressive growth of the stem, and the production from it of buds or gemmae, which gradually develop into mature animals, no doubt can be entertained either as to the vitality of this part, or of the direct communication between it and the young animals, at least up to the period at which they begin to emerge from their cells and to seek nourishment for themselves. Nor is it reasonable to suppose that this communication ever after ceases, for then it would be impossible to account for the nutrition of the growing parts, and the combined operations by which the regularity of growth of the whole is maintained, as exemplified in the ramified species by the proportionate thickening of the stem to the number of branches which it has to bear, and in the definite forms which each species assumes. But it might be questioned whether the whole of the stock is a living part, or only the soft interior; while the more dense exterior, together with the cell, might be re- garded as a mere exudation from it. From the various phsenomena, however, that occur during the growth of these parts, and from the manner in which they are blended in their early state, I am disposed to consider both the one and the other as organized and influenced by one common vitality. The two processes of reproduction here observed offer many points of contrast. That by gemmae, or buds from the common stock, appears to be uninfluenced by season ; the young animals, from the earliest period in which form can be traced in them, resemble in some measure the parent ; and their subsequent growth is but a deve- lopment of that form, and at no period are they separated from the parts that pro- duce them. The process by locomotive ciliated gemrnules is limited to certain sea- sons, generally spring ; these bear no resemblance to the parent ; they appear to be the more immediate produce of the individuals, than of the community ; and they 416 DR. A. FARRE ON THE STRUCTURE OF THE CILIOBRACHIATE POLYPI. separate from the parent at an early period, and must undergo metamorphosis before arriving at maturity. This process of reproduction is entitled to be called gemmuli- parous as contradistinguished from the gemmiparous mode. The gemmiparous mode is precisely similar to that which takes place in the free Hydra. The resemblance is nearest when there is no connecting stem, as in Mem- branipora, Cellarict, &c. Here the gemmae sprout apparently only from the cells, but doubtless also in connection with the parts of the body by which they are lined. When a stem is present the gemmae do not arise from the cells, but always from this, which is but an extension of the reproductive surface. In either case the buds are at first homogeneous throughout, and their separation into cell, parietes, and alimentary canal, is a subsequent process of growth. With regard to the mode by ciliated gemmules, it would be important to ascertain the origin and exact condition of these previous to their separation; and also to de- termine whether they have any relation with the brown bodies so frequently observed in the visceral cavity. These latter I found sometimes, after being kept several days, converted into mere cysts full of living animalcules, which however bore no re- semblance to the mature gemmules. Quitting, then, at this stage of the inquiry the further consideration of this type of structure, it will follow next in order to show what position it will hold with reference to other portions of the animal kingdom ; and for this purpose it will be necessary to consider the relative value of its different characters. In the absence of a knowledge of the condition of the nervous system, the cha- racters, at once the most obvious and important, are derived from the apparatus for entrapping and digesting the prey ; and the structure of the tentacula, and the form % of the alimentary canal, will of themselves be sufficient to constitute the distinguish- ing features of this type, connected too as the former appear to be with the very im- portant process of respiration. Indeed the combination of ciliated tentacula with a free alimentary canal, having two external openings, appears so uniform, that the pre- sence of the one being determined, the structure of the other, and indeed more or less of the entire animal, may be fairly inferred. With this view of the subject I propose for this class the name Ciliohrachiata, a name which, by seizing one of the most prominent features, will serve at once to di- stinguish those animals, to which it is applicable from all inferior types. The Ciliohrachiata, therefore, will comprehend the fourth family of Polypes of Milne Edwards, the Bryozoa of Ehrenberg, and the Polyzoa of Thompson ; and in applying a new name to a group of animals previously, but imperfectly, indicated by others, I do so with a wish to stamp upon it those distinguishing features which it has been my object in the present essay to point out, and in preference to adopting others which, as expressive of characters common to it with inferior types, might only tend to carry on the errors that have given rise to so much confusion with regard to the subject. DR. A. FARRE ON THE STRUCTURE OF THE CILIOBRACH1ATE POLYPI. 417 With a view to a subdivision of this class, after a more natural method than has hitherto been followed in arranging the various forms of Polypes, it would be desirable to regard the varieties presented by the alimentary canal, which from the conspicuous position of the parts are the more easily determined. Thus the presence or absence of the manducatory organ are points of much importance ; and the position of the anus may be also worthy of consideration. The structure of the alimentary canal, however, will probably be found to present but few essential points of difference, and it may be necessary soon to revert to the form of the cell as a secondary means of distinction. The position of the aperture and the character of the operculum then becomes of consequence, especially in its mode of termination, whether by separate spines or by a notched or smooth margin. But if it be found that where the aperture of the cell is lateral the manducatory organ is sometimes present, and in other cases absent, as I have shown it to be when the aperture is terminal, then the character of the cell must yield in importance to that of the alimentary canal, and the animals be arranged accordingly. With the lateral position of the aperture the operculum is generally simple, and the cells have seldom a distinct connecting medium. But where the aperture is terminal the operculum is more complicated, and the cells are generally united by a ramified or creeping stem ; but the passage from the one form of arrangement to the other is shown in Halodactylus , in which the cells, though usually placed perpendicularly with their sides in contact, and the aperture terminal, are yet sometimes placed so obliquely as to resemble in arrangement an encrusting species, having the aperture directed laterally. The structure of the cell, however, is not in this case affected by its accidental position. It will then be of consequence to determine the degree of importance to be attached to those characters which have been erroneously considered primary, namely, those that are derived from the common mass, or polypary. These, however, are generally the most superficial and least important ; since a very slight alteration in the arrange- ment of similar parts will give a very different character to the whole, as exemplified in the readiness with which an encrusting species might be converted into a ramified, and that again into a foliaceous one. But the mode of growth of the stem might oc- casionally afford useful characters for generic distinctions ; thus the definite mode of growth in Vesicularia spinosa is contrasted with the irregular arrangement of the cells in Bowerbankia and Lagenella ; whilst trivial characters are readily found in the number of the arms, and similar points of inferior importance. In natural affinities Ciliobrachiata is evidently allied both to Tunicata and Rotifera. In Tunicata the tentacles are reduced to mere rudiments at the entrance to the re- spiratory sac, and the cilia are distributed over the surface of this cavity, which is in proportion magnified, and is analogous to the pharynx of Ciliobrachiata. The more immediate entrance to the alimentary canal, thence called mouth, being situated at the bottom of this sac, corresponds with the part that I have called cardia ; and the analogies between the remaining course of the alimentary canal, position of the ovary, 418 DR. A. FARRE ON THE STRUCTURE OF THE CILIOBRACHIATE POLYPI. nature of the external covering, and other points of resemblance between the two classes, are easily traced. But between Ciliobrachiata and Rotifera the affinities are still nearer. Taking Hydatina as the representative of the latter class, the cilia (which, however, differ in form) are placed on short lobes instead of arms. The pharynx is very short, and leads at once to the manducatory organ, which guards the entrance to the stomach, as in Bowerbanhia. The muscular apparatus for altering the form of the body is identical in the two classes, and in the general character of the body and position of the contained parts there is a very close resemblance. They vary, however, in their inode of reproduction, position of the anus, and other points. The Ciliobrachiate polypes being thus separated from the rest of their associates by characters well defined and easily recognized, there yet remain two other types, which maybe represented by Hydra and Actinia, the Hydriform and the Actiniform , or Zoanthiform polypes. Of these two, the Hydriform polypes, whilst they are the furthest removed from Ciliobrachiata in degree of organization, are nevertheless those which have been most frequently confounded with them. For it would appear that in the lower type the superficial characters of the higher are sketched, as it were, in outline ; so that whilst they are found to differ materially in intimate structure, there yet remains a sufficient resemblance in external configuration to have caused them to be confounded together. The Hydriform polypes maybe recognized by the granular structure of the body, by the entire absence of a stomach distinct from the parietes, by the single external open- ing to the cavity, and the absence of cilia from the tentacula. The granular parenchyma of the body having a contractile power in every part, the alterations in its form and dimensions are effected without the necessity for a distinct muscular apparatus. No folding of the body takes place when the animals withdraw into their cells, where they are still left more or less exposed from the absence of a distinct operculum. The food is received at once into the main cavity of the body which constitutes the stomach, there to be acted upon by the granular parietes; and whilst the egesta escape by the same orifice by which they were taken in, as in Hydra , the nutrient particles have been traced to the tentacula in the free animals ; and in the compound ones as flowing in a stream through the tubular fleshy medium which communicates with the stomach, and by which all the animals are united. As in the higher type the tentacular cilia appear to be concerned both in nutrition and respiration, so their absence in the present case must be viewed with reference to both these points. With regard to the greater choice of food afforded by the action of cilia so placed, this appears to be less necessary where the body is of such a struc- ture as to be capable of accommodating itself to prey of a greater variety of size; whilst, for purposes of respiration, the exposure of the entire surface of the body to the water, which has free access to the cell, may be sufficient, without the necessity for that constant renewal of it that a more complicated organization appears to require. DR. A. FARRE ON THE STRUCTURE OF THE CILIOBRACHIATE POLYPI. 419 The absence of the ciliary character of the arms, in the present case, appears to be as uniform as its presence in the former ; and as so much of the economy of the animal turns upon this single point, one more characteristic could not perhaps be selected. 1 propose, therefore, to unite all those animals, which, partaking of the nature of Hydra, present this character, into a second class, to which the name Nudibrachiata might be applied. This class will comprehend the second family of polypes of Edwards, and the Di- morphcece of Ehrenberg. The more interesting forms of it have been so well illus- trated by the very interesting descriptions and figures of Mr. Lister, in the paper already referred to, that I have no occasion to add any here. The points in which Nudibrachiata approach nearest to Ciliobrachiata are (with the exception of the mere contour of the body), the general habit and mode of growth, and the process of reproduction. The former character I have shown to be extremely superficial, and one that should be considered as among the least important in a na- tural arrangement. It presents but little essential difference in the two classes. In the structure, however, of the more solid parts there appears to be a deficiency of the earthy material in the lower class, which in the higher is blended in greater or less quantity with the horny matter. The gemmiparous and gemmuliparous mode of reproduction appears to be similar in the two classes. The Nudibrachiata will probably continue to hold that position in the animal kingdom which has been usually assigned to the entire class Polypi. The class Polypi being* thus deprived of two of its principal divisions, which, whilst they resemble each other so much in superficial character, as to require the aid of the microscope to distinguish them, in their intimate structure hold the two extreme positions ; the third division only remains. But this is by far the most ex- tensive, and the animals are seldom or never so small but that their characters may be readily discerned by the unassisted eye, while many attain a considerable size. This division corresponds with the third family of Polypes of Edwards, and forms the Anthozoa of Ehrenberg, (deprived of the Plydrae and Sertularice ,) as last con- stituted by him. In this state I shall leave it, merely adding a few remarks on its natural affinities which necessarily arise out of the consideration of the two former classes, and in order to complete the view of the subject. The Anthozoa will comprehend the corticiferous polypes, together with the free and associated Actiniae, and indeed all those forms to which the familiar term “Ani- mal Flower” has been most frequently applied. The body is here distinctly membranous, and the stomach forms a separate pouch suspended in its centre. The stomach has but one external orifice, which serves for mouth and anus ; but posteriorly it communicates with the main cavity of the body. This, in Actinia, is divided perpendicularly by septa, passing from the stomach to the sides of the body ; and with the chambers thus formed the short tubular arms that are set round the mouth communicate. In these tubular processes a constant circu- 3 I MDCCCXXXVII. 420 DR. A. FARRE ON THE STRUCTURE OF THE CILIOBRACHIATE POLYPI. lation of fluids may be observed passing up from the chamber of the body and re- turning to it again. They appear to answer the double purpose of prehensile tenta- cula and of respiratory tubes. They are not ciliated externally*, and in form have little resemblance to the tentacles of the other two classes. In this respect, however, they vary very much, being, in some forms of Actinia , arranged simply in one or more circles round the mouth ; in others, elevated upon semilunar lobes ; whilst, in other instances, as in Xenia, Gergonia, &c., these lobes may be supposed to be drawn out into the conical or cylindrical arms, having a dentated margin ; in which cases the whole arm does not correspond with a single arm of Actinia, but each of the den- tiform processes upon its sides. The character of distinct ovaria producing ciliated gemmules appears to be very prevalent through this class. The Anthozoa, then, are distinguished from Nudibrachiata chiefly by the separation of the stomach from the parietes of the body, which has a membranous character ; and from Ciliobrachiata by the single external opening, and the absence of cilia from the surface of the arms. They appear to hold a place immediately below Acalepha and Echinodermata, the transition between these three classes being exceedingly gradual. Thus, with Asterias, the affinities are easily traced. The single external opening to the membranous stomach is found equally in Actinia and Asterias ; but while in the former this organ communicates posteriorly with the main cavity of the body, in the latter it is closed in this position, and the immediate communication cut off. Again, in the conical arms of the corticiferous polypes, with their fringe of tubular processes, may be traced the analogue of the rays and respiratory tubes of Asterias ; both are distended by the fluids which circulate through them, probably for respiratory pur- poses. Moreover, in the position and form of the ovary the closest resemblance exists ; and when to these points is added the stem of the crinoid animals, the affi- nities between the two classes are rendered still more striking. Again, between Anthozoa and Acalepha analogous points of resemblance might be traced ; and here again the transition appears so gradual that it might be difficult to determine where the one ends and the other begins. Thus, then, it appears that under the commonly received name of Polypi there exist three distinct types of structure, which must be referred to the same number of separate classes, possessing but few points in common, and those generally of the most superficial kind, but which have nevertheless induced naturalists, from the want of a sufficient degree of attention to their intimate structure, to group together, in ac- cordance with such superficial resemblance, animals that have no title to be clas- sically associated. * It might be objected that as the arms of Anthozoa are not ciliated, at least externally, the term “ Nudi- brachiata” is equally applicable to this class. The Anthozoa, however, could never be confounded with either of the other two classes, to the mutual distinction of which the names that I have applied to them have re- ference. //£«/. frgjzj. MD C C CJi&X.VIL . ffobfa, XT p.^Zf. G^MiraWwaBa ' TarciASitu: on /’luxStra.' fblwbc mo Bowe-rbocnhbot/ tfcriASOo .JrlJiAAr Farr* cU/r JfiaMT' Fftzl. 7rans MD CCCMXV1L ./iaUl^L i jt.+ZJ. Fig. f£ X 100 V / " - - ■'■'■*• 3owerbfl/n. fu*J/ deswas. Czlwfrradvuitii' Vejas. TAor 4- * 300. %6- xioo. A/uf fc;MD CCCaXXV \X.7Za&JKN.p Artful' Aar r is AsA (Xlswbrajakiycofa. /Visits, /rertui. M DCC C XXX YU . f lafo XX V 1 p 4-2/. ArtA^/rlhrrc. dtl. Jlfamtira-rujpora, piloscu. .BI^cutiv. Gyliolra^h/ilay. fkd, Ircu/us. MD CC C AXXVli FlaieJSS^Lp. -fZi JVo7xim]M/ IflrTPiijlcCtxv. JJhirirc, ti/A DR. A. FARRE ON THE STRUCTURE OF THE CILIOBRACHIATE POLYPI. 421 Description of the Plates*. The linear enlargement of each figure is expressed by the numbers with the sign x prefixed. ClLIOBRACHIATA. Plate XX. and XXI. fig. 1 to 16. p. 391. Bowerhanhia densa. Fig. 1. a. h. Fig. 2. X 40. Fig. 3. X 80. a. b. c. d. Fig. 4. X 80. A specimen of the natural size, with the creeping stems closely set upon a piece of Flustra foliacea. A portion of the same separated. The same as fig. 1 . b. The animals are seen in various positions, and in all stages of growth. One of the animals fully expanded. 1. Pharynx. 2. Cardia. 3. Man- ducatory organ, or gizzard. 4. Stomach, its parietes studded with the hepatic follicles. 5. Pylorus. 6. Intestine, containing pellets of feculent matter. 7- Anus. The gastric (8) and tentacular (9) retractors are seen within the cavity of the body. The flexible por- tion of the cell, or the operculum, is seen expanded and surrounding the upper part of the body. A similar animal completely retracted. The stomach drawn to the bottom of the cell. The upper portion of the alimentary canal flexed. The tentacula somewhat distorted by the pressure of the operculum. Their retractor filaments relaxed, 1 . The upper part of the cell is occupied by the operculum folded up in its axis, and from it the upper and lower sets of opercular retractors are seen radiating, and in their contracted state. 2 and 3. These filaments are about inch diameter in this state. An immature animal. The tentacula and alimentary canal rudely formed ; the cavity in the latter very distinct. The tentacular and opercular retractors also shown. 1. The gizzard. One of the gemmse in its earliest state. The cavity just defined, but no animal distinguishable. Portion of the alimentary canal, showing very distinctly the cardia. Gizzard with the dark points, radiating lines and teeth. Hepatic follicles and pylorus. * In the representation of specimens of the natural size, I have in most cases selected such small portions as may be just sufficient to afford a recognition of the species, to avoid encumbering the plates with points which are of minor importance, and which, moreover, would be unsuited to pages not devoted to zoological subjects. This remark is particularly applicable to the figure of Halodactylus , PI. XXV. 1., which conveys no idea of the size to which the aggregate masses sometimes attain. 3 i 2 422 DR. A. FARRE ON THE STRUCTURE OF THE CILIOBRACHIATE POLYPI. Fig. 5. X ISO. Fig. 6. X 180. Fig. 7. Fig. 8. Fig. 9 to 1 1. Fig. 9. Fig. 10. Fig. 1 1. Fig. 12. Fig. 13. Fig. 14. Fig. 15. Fig. 16. a. b. The gizzard relaxed, with the dark bodies or constrictor muscles seen on opposite sides, and projecting into its cavity. The inner surface lined with teeth. The same in a state of contraction. The dark bodies elongated and brought into apposition, obliterating the cavity. (Both these figures as seen when the interior of the organ is in focus.) The gizzard torn open, and the teeth displayed. Portion of the pharynx, with the markings upon its surface. A series to show the mode in which the operculum and upper part of the body is unfolded. The same animal is represented in four dif- ferent stages. First stage. The top of the cell completely closed. The setae, folded up in the centre, 9 a, with the flexible portion of the cell b inverted and closely surrounding them. The muscles contracted, d d. Second stage. The bundle of setae a rising from the centre of the cell, being forced upward by the pressure of the tentacula. The flexible portion b rolling from around the setae, and the muscles d put upon the stretch. Third stage. The flexible portion b completely everted. The setae a still lying together. The tentacles just appearing between them. Fourth stage. The tentacula appearing above the margin of the oper- culum. The integument of the body, which forms the tentacular sheath half everted, c. The operculum completely expanded. The letters refer to the same parts in all. The last stage is seen in fig. 3. a. where the eversion of the integument is complete and the tentacula separated. (These stages are taken arbitrarily, the process being continuous.) The parietal muscles which assist in the act of protrusion. The knot is seen in the centre of each. Showing the position of the brown and white bodies. (Query, ova.) The same in a young animal. Two of these separated from the body. More highly magnified, showing the external membranous sac with contained granular matter. Plate XXII. p. 401. Vesicularia spinosa. Fig. 1 . X 3. A portion of the stem with the branches springing from its angles. Fig. 2. X 40. Small portion of a growing branch. The cells strictly unilateral, and DR. A. FARRE ON THE STRUCTURE OF THE CILIOBRACHIATE POLYPI. 423 showing1 a regular gradation in growth. The apertures are seen left by the falling off of the cells, and below them the apparent line of connexion. The stem occupied by granules. Fig. 3. X 100. The animal expanded (not very perfectly). The arms and alimentary canal short compared with the former species. The gizzard and other parts the same. The parietes seen separated from the cell at a. Fig. 4. A similar animal in the act of protruding. Fig. 5. Another completely retracted. The parietal granules seen in each of these figures. Fig. 6. A young animal. Fig. 7- Upper half of a cell, showing the setae. Fig. 8. Two animals, showing the various muscles. a. Gastric retractors. b. b. Tentacular retractors, c. c. c. Parietal muscle. d. d. d. d. Opercular retractors. Plate XXIII. p. 402. V alkeria cuscuta. Fig. 1. Natural size. Growing on Ceramium, like Dodder. Fig. 2. X 6. A similar portion separated. Fig. 3. X 40. Two portions showing the arrangement of the cells. At a in groups surrounding the stem, and sessile. At b raised upon short branches from each joint. On a portion of Ceramium. Fig. 4. X 100. Group of animals. a. Expanded b. Retracted. This figure shows also the opercular retractors, the brown body and the parietal granules. These two latter are also seen in the cell c, which in other respects is empty. Fig. 5.X 250. Single animal magnified to show the cercariae in the cavity of the body. g. Separate cercariae. a. Tentacula. b. Line in the pharynx. c. Stomach. d. Pylorus. e. Rectal enlargement of intestine. f. Operculum protruding. 424 DR. A. FARRE ON THE STRUCTURE OF THE CILIOBRACHIATE POLYPI. Parietal granules and muscles distinct. The gizzard wanting in this and all the following species. Fig. 6. Empty cell showing the operculum terminating in setae. Plate XXIV. p. 403. Lagenella repens. Fig. 1 . Natural size, parasitic on Sertularia. Fig. 2. X 40. Portion of the same. The animals in various positions and stages of growth, connected by a creeping stem, and mixed with Membrani- pora pilosa. a. Side of the cell indented by the pressure of the surrounding fluid when the animal protruded. Fig. 3. x 100. a. Animal protruded. 1. Triangular space in the pharynx. 2. Stomach during digestion. The hepatic follicles large and very distinct. The food tinged with their secretion. The pylorus well marked. 3. Pa- rietes separated from the sides of the cell by the action of the pa- rietal muscle. 4. Notched margin of operculum. b. and c. Two animals retracted. The operculum drawn towards one side by the single retractor. The stomach suspended by the intestine from the top of the cell ; at b 2. the stomach is seen pale and empty, and the hepatic follicles barely visible, b 3. Parietal muscles. This figure ( b .) exhibits the appearance invariably presented by all the animals of this class when they have remained for a day or two without emerging from their cells, and consequently without a fresh supply of food ; emptiness of the stomach, being in every case accompanied by a pale and nearly transparent state of its parietes, and a reduction of the follicles to the finest points ; while the full stomachs appear as represented at a. These characters are so striking when pervading an entire specimen, as at a glance to fur- nish the observer with a ready test of the purity of the water em- ployed, and of the degree of vigour of the little animals under examination. d. Figure showing the muscles. 1. Gastric. 2. Tentacular and 4. Oper- cular retractor. 3. Two sets of parietal muscles. e. e. e. Geinmse in various stages. Fig. 4. Parietal muscles in a state of relaxation. Fig. 5. The same in a state of contraction. Their diameter doubled. DR. A. FARRE ON THE STRUCTURE OF THE CIUIOBRACHIATE POLYPI. 425 Plate XXV. and XXVI. p. 405. Halodactylus diaphanus. Fig. ]. A small specimen of the natural size. The animals seen protruding from its surface. Fig. 2. X 40. The appearance presented by a lateral view of the surface. The ani- mals in various stages of protrusion. Their diameter doubled. Fig. 3. X 40. Thin transverse section of fig. 1. The centre occupied by a cellular tissue and water. The circumference formed by the cells in close apposition. The brown bodies scattered through the substance. a. a. Position of the gemmules, enclosed in the sac. b. One of the gemmules escaped during the section into the central tissue. Fig. 4. X 80. Thin slice from the surface, with a terminal view of the cells, showing their mode of arrangement, and various stages of growth. Fig. 5. x 80. A similar slice from a specimen which afforded a lateral view of the cells, as in Flustra. The muscles and granules distinct in both figures. Fig. 6. x 80. A young animal extracted, rudely formed. The cavities in the ali- mentary canal and arms are very distinct. Fig. 7- X 80. Group of animals. ( Lateral view of the surface as in fig. 2.) a. Fully expanded. The arrows mark the direction of the particles of carmine, in the currents produced by the ciliated arms. b. The arms turned over the margin of the cell as if to feel, preparatory to the entire protrusion of the animal. c. Animal nearly retracted. d. Empty cell. Fig. 8. Pharynx, with portion of tentacula. a. Pharyngeal line. b. Cardia. d. Constricted portion of pharynx ; above are seen the tubes in the arms and the apertures at their base. Fig. 9. The pharynx, with squamiform spots, triangular space, c. and dark line, a. Fig. 10. Appearance of a circumferential vessel in the tentacular ring. Fig. 11 to 16. A series illustrating the act of protrusion at different stages; at a. figs. 14, 15 and 16 is a circular band within the setse, apparently for the purpose of bringing them together, seen contracted at a 13. b 15. Integument half inverted, forming tentacular sheath. Fig. 16. b. Flask-shaped body. Lateral view. The arrow denotes the course of the ciliary motion. This specimen shows the oblique termination of the tentacula. 426 UR, A. FARRE ON THE STRUCTURE OF THE CILIOBRACHIATE POLYPI. Fig. 17. b. Posterior view of flask-shaped body. Fig. 1 8. b. Anterior ditto. (The cilia are not represented in these latter figures ; they are seen in fig. 7.) Fig. 19. a. Portion of recent arm. The cilia very numerous. b. c. The same when perishing. Fig. 20. X 40. a. Sac containing gemmules. b. Single gemmule in the act of swimming, with the cilia curved down- ward. c. The same viewed from above. The waves of cilia appearing as single cilia. Fig. 21. X 100. A gemmule seen from the under surface. The greater part of the cilia folded up. The muscular lobes shown. a. The cilia that have a distinct motion from the rest. Fig. 22. The same from above. The cilia as when slowly acting round the margin in waves. The muscular lobes more distinct. Fig. 23. The appearance of the cilia when in rapid action. Fig. 24. The same after forty-eight hours, when it has become fixed and the formation of the cell commenced. Plate XXVII. fig. 1 to 5. p. 412. Membranipora pilosa. Fig. 1. Three animals in different positions. A fourth growing at e. a. Anus. b. Margin of operculum. These were parasitic on the filaments sur- rounding the stem of Vesicularia spinosa. Fig. 2. Circumferential and tentacular canals. Figs. 3 and 4. Flask-shaped body. Fig. 6 to 9. p. 413. Notamia loriculata. Fig. 6. A branch of the natural size. Fig. 7- X 10. Portion of ditto. Fig. 8.X 100. a. Animal fully formed. Pylorus and rectal enlargement very distinct, the latter distended by feculent matter. b. Young animals. c. Buds yet homogeneous in texture. Fig. 9. Animals in different stages of protrusion. a. Horse-shoe aperture in membranous operculum. [ 427 ] XXIII. On the Ipoh or Upas Poison used by the Jacoons and other Aboriginal Tribes of the Malay Peninsula. By Lieut. T. J. Newbold, A.D.C. to Brigadier-General Wilson, C.B. Communicated by P. M. Roget, M.D. Sec. R.S. Received January 26, — Read June 15, 1837. To tip the slender arrows propelled from the Sumpitan, or blow-pipe, the aborigines of the Malay Peninsula make use of three preparations of the Ipoh or Upas poison, distinguished by the names Krohi, Tdnnik or Kennik, and Malldye. The Krohi is extracted from the root and bark of the Ipoh tree, the roots of the Tuba and Kopah ; red arsenic and the juice of limes. The Tdnnik is made in the same manner as the Kr6hi, leaving out the Kopoh root. The Malldye poison, which is accounted the most potent of the three, is prepared from the roots of the Tuba , the Perachi , the Kopah and the Chdy, and from that of the shrub Malldye-, hence its name. The process of concocting these preparations is as follows : the roots are carefully selected and cut at a particular age of the moon ; I believe about the full. The woody fibre is thrown away, and nothing but the succulent bark used. This is put into a quali (a sort of pipkin made of earth), with as much soft water as will cover the moss, and kneaded well together. This done, more water is added, and the whole is submitted to a slow heat over a charcoal fire until half the water has evaporated. The decoction is next strained through a cotton cloth, again submitted to slow ebul- lition until it attains the consistence of syrup. The red arsenic ( Warangan ) rubbed down in the juice of the sour lime, the Limou Assam of the Malays, is then added and the mixture poured into small bamboos, which are carefully closed up ready for use. Some of the tribes add a little opium, spices and saffron, some the juice of the Lanchar and the bones of the Sunggat fish burnt to ashes. A number of juggling incantations are performed and spells gibbered over the seething caldron by the Poyangs, (a class of men supposed by this superstitious race to be in league with the powers of darkness,) by whom the fancied moment of the projection of the poisoning principle is as anxiously watched for as that of the philo- sopher’s stone, or the elixir vitae by the alchymists and philosophers of more enlight- ened races of men. When recently prepared the Ipoh poisons are all of a dark liver brown colour, of the consistence of syrup, and emit a strong narcotic odour. The deleterious prin- ciple appears to be volatile, as the efficacy of the poison diminishes by keeping. The arrows are very slight slips of wood, scarcely the thickness of a crow-quill, 3 K MDCCCXXXVII, 428 LIEUT. NEWBOLD ON THE IPOH POISON. and generally about eight inches long, tapering to a fine point ; this is coated with the poison, which is allowed to inspissate thereon for the space of an inch or so. They then cut the arrow slightly all round at the part where the coat of poison ends, consequently it almost invariably snaps off on piercing the flesh of the victim, leaving the envenomed point rankling in the wound. At the other end of the arrow is a cone of light pith-like wood, which is fitted to the tube of the Sumpitan, and assists mate- rially in the propulsion and direction of the arrow. From experiments I caused some of the aborigines to make with these poisoned weapons on living animals in my presence, I am enabled to offer the Society the fol- lowing results, showing the efficacy of the Kennik preparation. A squirrel died in 12 minutes ; young dogs in from 3 7 to 40 minutes ; a fowl in two hours : one lingered hours. Three arrows tipped with the Mallaye preparation, it is affirmed, would kill a man in less than an hour, and a tiger in less than three hours. According to the aborigines the only remedy against the poison is the recent juice of the Lemmah-kapiting, rubbed round and into the wound, and afterwards over the limb into which the puncture has been made. The arrow seldom penetrates farther than an inch, snapping off as mentioned above. The following are the symptoms evinced by a strong healthy pup, struck in the right hip ; penetration of the arrow about one fourth of an inch only. Six minutes after being wounded it demonstrated signs of uneasiness, yawned and moaned. In 10^ minutes it grew sick ; vomited the contents of the stomach ; continued vomiting at intervals, bringing up small quantities of a white frothy-looking fluid. In 16 mi- nutes the muscles of the chest and diaphragm were powerfully excited ; slight convul- sive twitchings in the legs. In 20 minutes it fell on its side, foamed much at the mouth ; again got on its legs, and struggled violently as if to get loose. In 23 minutes it was still foaming at the mouth, and had an involuntary alvine evacuation ; it then again fell down after painful retching, made ineffectual attempts to vomit, and continued in this state, the efforts to relieve the stomach and chest gradually becoming weaker, till at 37 minutes after the insertion of the poison it died strongly convulsed. On dissection by Mr. Maurice, the surgeon of the 23rd Regiment, M.N.I., a frothy saliva-like fluid was discovered in the stomach ; the gall-bladder distended with bile ; the intestines unusually pale. In the cavity of the thorax on each side were found about four drachms of a serous fluid. The brain and spinal chord, I regret to say, were not examined. By reason of the complicated nature of its preparation, it would be difficult to de- cide from the above train of symptoms whether the Upas poison should or should not be classed, as it has been by some writers, among the narcotico-acrid vegetable poisons. Quere, whether the Lemmah-kapiting, a shrub said by natives to be the only anti- dote against it, bears any botanical affinity to the Feuillea cordifolia, ascertained by Monsieur Drapiez to be a most powerful antidote agains vegetable poison. The LIEUT. NEWBOLD ON THE IPOH POISON. 429 native names of the plants I have mentioned will, it is hoped, afford botanists visiting the Straits of Malacca, or the islands of the Indian Archipelago, some clue to a more scientific investigation, both of the plants of which the poison is composed, and of its antidote, the Lemmah-kapiting. With regard to the Ipoh tree of the Malay penin- sula, from the description of it given to me by the natives, I much question its iden- tity with the Anchar or Upas tree of the Javan forests, described by Dr. Horsfield, and the Arbor toxicaria of Rhumphius. It may be superfluous to add, that in the wildest tales related to me by the abo- rigines regarding the deadly qualities of this poison, there is nothing to corroborate or give rise to the extravagant fictions with which Foersch so easily amused the cre- dulity of half Europe. Bellary, Madras Presidency , August 7, 1836. ■ ’ v9 : nfll , ' ' ' !‘«r " :•< ■ ' . • " . . [ 431 ] XXIV. Description of a new Barometer, recently fixed up in the Apartments of the Royal Society ; with Remarks on the mode hitherto pursued at various periods, and an account of that which is now adopted, for correcting the observed height of the mercury in the Society's Barometers. By Francis Baily, Esq. Vice-President and Treasurer R.S. Received October 25, — Read November 16, 1837. The Barometer here alluded to may in some measure be considered as two sepa- rate and independent barometers, inasmuch as it is formed of two distinct tubes dip- ping into one and the same cistern of mercury. One of these tubes is made of flint glass, and the other of crown glass, with a view to ascertain whether, at the end of any given period, the one may have had any greater chemical effect on the mercury than the other, and thus affected the results. A brass rod, to which the scale is at- tached, passes through the framework, between the two tubes, and is thus common to both : one end of which is furnished with a fine agate point, which, by means of a rack and pinion moving the whole rod, may be brought just to touch the surface of the mercury in the cistern, the slightest contact with which is immediately discern- ible* ; and the other end of which bears the scale of inches, on which I have set off with great accuracy, from the standard scale of the Royal Astronomical Society, the distance of 30 inches from the above-mentioned agate point. Above and below this mark of 30 inches, the usual scale of inches, tenths, &c. is engraved ; and there is a separate vernier for each tube. A piece of thin brass projects from the zero point of each vernier, across its contiguous tube, which, when the height of the mercury is read off, is brought down so that the lower edge of it forms a tangent to the column of mercury, in the usual manner. A small thermometer, the bulb of which dips into the mercury in the cistern, is inserted at the bottom : and an eye-piece is also there fixed, so that the agate point can be viewed with more distinctness and accuracy. The whole instrument is made to turn round in azimuth, in order to verify the per- pendicularity of the tubes and the scale. It is evident that there are many advantages attending this mode of construction, which are not to be found in the barometers as usually formed for general use in this country. The absolute heights are more correctly and more satisfactorily determined ; and the permanency of true action is more effectually noticed and secured. For, every part is under the inspection and control of the observer ; and any derangement or * The motion of this rack-work is much too slow, and might be greatly improved if made more rapid. 432 MR. BAILY’S DESCRIPTION OF A NEW BAROMETER. imperfection in either of the tubes is immediately detected on comparison with the other. And, considering the care that has been taken in filling the tubes, it may justly be considered as a Standard Barometer. The specific gravity of the mercury was determined by Dr. Prout to be 13*581 ; the thermometer being at 62°, and the barometer at 30 inches*. The second part of the present volume of the Philosophical Transactions will con- tain the first register of the observations that have been made with this instrument. The daily observations are recorded just as they are read off from the scale, without the application of any correction whatever. This will be found, on due consideration, and after the details which I shall presently state, to be the most simple, and by far the safest plan of registering them ; whatever mode may be afterwards adopted of re- ducing and discussing them. At the end of each month the uncorrected mean is de- duced ; which mean, however, will also be given corrected agreeably to the usual formulae, to which I shall now proceed to advert. The observed height of the mercury in a barometer requires several corrections (differing according to the construction of such barometer) in order to determine its absolute height, or that point when it may be considered strictly comparable with another barometer, either of the same or of a different construction : and, for effecting this end, certain conditions are previously understood, and universally assented to. Thus, the temperature of the mercury is always supposed to be at the freezing point of water, or 32° Fahrenheit : the scale, by which the height is measured, if liable to expansion by heat, is always reduced to the standard temperature, which in this country is 62° Fahrenheit : the tube must be corrected for its capillary attraction : and lastly, proper allowance should be made, in certain cases, for the elevation of the place of observation above the mean level of the sea. I shall speak of each of these in their order-f-. With these corrections duly made, the absolute heights of two baro- meters might be considered comparable with each other, although separated by the whole diameter of the globe : and with barometers, formed of tubes of a considerable diameter, and having a well adjusted scale, this is probably the case. Yet as, even in the best barometers, there are still certain sources of discordance, some of which, although slight, cannot be altogether avoided notwithstanding our utmost care, such as differences in the specific gravity of the mercury, or in setting off the measure of the scale, or an uncertainty in the height of the station above the mean level of the sea, and, in the more usual ones, others of a more formidable and variable nature, depending on circumstances not yet sufficiently accounted for, it is always the most * Dr. Prout has been good enough to inform me that, in taking the specific gravity of mercury in the common mode, it is necessary, in order to expel the whole of the adhering air, to heat repeatedly the mercury in the vessel to nearly the boiling point, and in this state to expose it under the exhausted receiver of an air-pump. This precaution was taken in the present instance. f In those barometers where the tube dips into a measured cistern (similar to that which was constructed for this Society by Mr. Daniel, to which I shall presently allude) there is another correction requisite, which depends on the relative capacity of the tube and the cistern : but this does not apply to the present barometer MR. BAILY’S DESCRIPTION OF A NEW BAROMETER. 433 satisfactory method to compare them together, if possible, on the same spot, more especially where great accuracy is required*. The correction for the temperature of the mercury is by far the most important, since it is in most cases more than ten times the amount of the correction for the expan- sion of the scale. The correction, for both these sources of discordance and error, may be reduced to one general expression by the following well-known formula : viz. , m (t — 32) — s (t — 62) ^ 1 + m (t — 32) where h denotes the observed height, as read off from the scale, which represents En- glish standard inches when at the temperature of 62° Fahr., m the expansion of mer- cury in volume, and s the expansion of the scale in length, for 1° Fahr. : t denoting the temperature of the mercury and the scale, which are supposed to be the same, and to be ascertained by the thermometer that dips into the cistern of mercury ; the slight dilference which may exist in the temperature of the scale making no perceptible difference in the results. According to the accurate experiments of MM. Dulong and Petit, it appears that mercury expands in volume (=*000100100) for each degree of Fahrenheit’s thermometer : and, with respect to the linear expansion of brass (of which the present scale is made) we may assume it to be *000010434 for each degree of Fahrenheit. Consequently the above formula becomes , % > -0001001 ( t — 32) — -000010434 ( t — 62) “ h X 1 + -0001001 (t — 32) which, by proper reduction, becomes •000089566 t — -002553092 h X -0001001 t + -9967968 This expression may be easily formed into a table of double entry, which would be very convenient for correcting the observed heights of the barometer. And it is agree- ably to this formula that Professor Schumacher has constructed the tables which are printed in the first volume of his Astronomische Hiilfstqfeln, showing the correction for every difference of half an inch in the height of the mercury, from 27^ to 31 inches; and for every degree of Fahrenheit from 6° to 88°, to four places of decimals. These tables, having been afterwards slightly corrected, were (together with some others) printed on a separate sheet, and distributed with No. 114 of his Astronomische Nach- richten. They have been recently much enlarged by the distinguished author ; and * In one of my barometers, the tube of which is about a quarter of an inch in diameter, the mercury has generally stood about a quarter of an inch lower than that of a standard barometer placed by its side, after every correction made for capillarity and temperature, and after a careful examination of the scale. I satisfied myself that there was no air in the tube ; having had it re-filled with mercury for the express purpose of determining that point, and having also placed it by the side of other excellent standards, and always with the same results. This anomaly, I have since been informed, is by no means rare, and shows the necessity of direct comparison of such barometers with standard ones. Mr. Newman however conceiving that the imperfection arose from vapour, has remedied it by drying and wiping out the tube and filling it again with heated mercury. 434 MR. BAILY’S DESCRIPTION OF A NEW BAROMETER. having been extended to every tenth of an inch in the height of the mercury, and to every fifth part of a degree of its temperature, are now printed in his Jakrbuch for 1837- It is by these latter tables that the monthly means, in the Meteorological Register, are now corrected for temperature. As I am not aware that any tables of this kind have been printed in England, I shall (with the approbation and consent of the author) give, on this page, some of the values here mentioned : namely, for every half inch in the height of the mercury from 28‘0 to 30-5 inches, and for every degree of its temperature from 30° to 90°, which will be found very useful and convenient for the correction of such barometers as are furnished with a continuous brass scale*. Corrections for a Mercurial Barometer with a continuous Brass scale : all subtractive. Ther. in. 28-0 in. 28-5 Baror in. 29-0 neter. in. 29-5 in. 300 in. 30-5 Ther. in. 28-0 1 in. 28-5 Baro in. 29-0 meter. in. 29-5 in. 300 in. 30-5 O 30 •004 •004 •004 •004 •004 •004 o 60 •079 •080 •082 •083 •084 •086 31 •006 •006 •006 •007 •007 •007 61 •081 •083 •084 •086 •087 •089 32 •009 •009 •009 •009 •009 •009 62 •084 •085 •087 •088 •090 •091 33 •Oil •011 •012 •012 •012 •012 63 •086 •088 •089 •091 •092 •094 34 •014 •014 •014 •014 •015 •015 64 •089 •090 •092 •094 •095 •097 35 •016 •017 •017 •017 •017 •018 65 •091 •093 •095 •096 •098 •100 36 •019 •019 •019 •020 •020 •020 66 •094 •095 •097 •099 •100 •102 37 •021 .022 •022 •022 •023 •023 67 •096 •098 •100 •101 •103 •105 38 •024 •024 •025 •025 •025 •026 68 •099 •101 •102 •104 •106 •108 39 •026 •027 •027 •028 •028 •029 69 •101 •103 •105 •107 •108 •110 40 •029 •029 •030 •030 •031 •031 70 •104 •106 •107 •109 •111 •113 41 •031 •032 •032 •033 •034 •034 71 •106 •108 •110 •112 •114 •116 42 •034 •034 •035 •036 •036 •037 72 •109 •111 •113 •115 •116 •118 43 •036 •037 •038 •038 •039 •040 73 •111 •113 •115 •117 •119 •121 44 •039 •039 •040 •041 •042 •042 74 •114 •116 •118 •120 •122 •124 45 •041 •042 •043 •044 •044 •045 75 •116 •118 •120 •122 •124 •127 46 •044 •045 •045 •046 .•047 •048 76 •119 •121 •123 •125 •127 •129 47 •046 •047 •048 •049 •050 •050 77 •121 •123 •125 •128 •130 •132 48 •049 •050 •051 •051 •052 •053 78 •124 •126 •128 •130 •132 •135 49 •051 •052 •053 •054 •055 •056 79 •126 •128 •131 •133 •135 •137 50 •054 •055 •056 •057 •058 •059 80 •129 •131 •133 •135 •138 •140 51 •056 •057 •058 •059 •060 •061 81 •131 •133 •136 •138 •140 •142 52 •059 •060 •061 •062 •063 •064 82 •134 •136 •138 •141 •143 •146 53 •061 •062 •064 •065 •066 •067 83 •136 •138 •141 •143 •146 •148 54 •064 •065 •066 •067 •068 •070 84 •139 •141 •143 •146 •148 •151 55 •066 •067 •069 •070 •071 •072 85 •141 •144 •146 •149 •151 •154 56 •069 •070 •071 •073 •074 •075 86 •144 •146 •149 •151 •154 •156 57 •071 •073 •074 •075 •076 •078 87 •146 •149 •151 •154 •156 •159 58 •074 •075 •076 •078 •079 •080 88 •148 •151 •154 •156 •159 •162 59 •076 •078 •079 •080 •082 •083 89 •151 •154 •156 •159 •162 •164 60 •079 •080 •082 •083 •084 •086 90 •153 •156 •159 •162 •164 •166 * By a continuous brass scale, I mean one that extends the whole length of the tube : and it should be spe- cially borne in mind that the tables, here alluded to, apply only to barometers of that construction. For baro- meters of the ordinary construction, other tables, computed also by Professor Schumacher, will be mentioned in the sequel. See the note in page 437. MR. BAILY’S DESCRIPTION OF A NEW BAROMETER. 435 The correction for the capillarity of the tube is very slight, and might indeed be safely neglected : but it has been considered proper that every source of anomaly, however* small, should be pointed out and scrupulously allowed for. The diameter of the tube of flint glass is '594 inch, and of the tube of crown glass ’658 inch. The correction for these, agreeably to the formula of Laplace, would be respectively + *0048 and + ”0033 : but, in cases where the mercury has been well boiled in the tubes, the correction, as found by the formula, should be somewhat diminished. If we strike off the last figure in each case, we probably shall not be far from the truth : and I have therefore proposed that the correction to be applied should be + ”004 to the flint glass, and + ”003 to the crown glass. These are all the corrections that, in the case of the present barometer, require to be applied in order to ascertain the absolute height at the place where it is now fixed. The correction for the height of a barometer above the mean level of the sea, is never applied except on especial occasions, and for some definite and express object. The formula for such correction, whenever it may be wanted, is as follows * : d= + — where d denotes the addition (in parts of an inch) to the height of the mercury in the barometer, when elevated f feet above the mean level of the sea, in order to show the height at which the mercury would stand, provided the barometer were placed at that level. So that, assuming the height of the station of the present barometer to be 9 7 feet above the mean level of the sea (and on this subject I shall have some further remarks to make in the sequel), the above expression would become ■ h a — 250-90 + *60 t Whence, if the reading of the barometer, at the place where it is now fixed, were ex- actly 30 inches, and the temperature 60°, we should have 30 d — + 286*9 = + '1045 * This formula is easily deduced from that which I have given in my Astronomical Tables and Formulae , page 111, for “ computing the difference in the height of two places by means of the barometer.” For, there we have / = a . b . c . log ~ b! all known quantities except h' . But log— is equal to log b! — log h : and if we make b' = h + d (where d is h the required difference in the height of the mercury) we have log b' = log h + M . The formula there- fore becomes whence we obtain which is the formula in the text. MDCCCXXXVII. f = a . b . c . M- f-h a . b . c . M 3 L 436 MR. BAILY’S DESCRIPTION OF A NEW BAROMETER. Or, in other words, the height of the mercury in the barometer would in such case be 30-1045 inches, if placed at the mean level of the sea, instead of being in the apart- ments of the Society: and so in the proportion of -0011 inch for every foot below its present position. But, as I have before remarked, this correction is wholly omitted in the Meteorological Journal. I have been particular in giving these explanations as to the precise mode in which the corrections should (and are now directed to) be made, since it appears that great irregularity, as well as some inattention, error, or confusion has hitherto occurred on this subject, which ought not to have existed ; and the Meteorological Journal of this Society has lost much of its utility, confidence, and importance in consequence thereof. Prior to the year 1823, the registers of the barometer do not indicate whether the observations are corrected or not : nor can I obtain any satisfactory information on this point. So that a person now referring to them can consider them only as ap- proximate values. The barometer then in use is still in existence. In January 1823 the registers commence (as I presume*) with the new barometer which had been constructed in the preceding year under the able direction of Mr. Daniel, now Professor of Chemistry at King’s College. A description of this baro- meter is given by him in his Meteorological Essays and Observations, page 353. The daily observations are, in the register, said to be corrected ; but no formula or rule is given, of the mode in which the corrections have been made: and if the observations have been corrected by the small table engraved on the face of the barometer (which is the same as that given by Mr. Daniel in page 372 of his Essays ), the result will in most cases, for the reasons which I shall presently mention, be slightly erroneous ; but more so as the temperature varies from the freezing point. So that although, during the winter months, the results will not be far from the truth, yet in the sum- mer they will not exhibit the correct values-f-. For, that table has been calculated “ from the expansion of mercury and mean dilatation of glass :” it having been origin- ally intended (as I have understood) that the divisions of the scale should have been cut on the glass tube. But this plan having been abandoned, and recourse had to the ordinary mode of construction, it is evident that the expansion of the glass tube does not affect the observed height of the column of mercury sustained by the atmosphere. The only effect which the expansion of the glass can have on the reading of the vernier, will be caused by an alteration in the relative capacity of the tube and the cistern ; but this would be so extremely small, on all ordinary occasions, as to be * There is nothing stated in the register by which we can judge whether the old barometer, or Mr. Daniel’s, was at that time used for the daily observations ; except that the height of the cistern of the barometer is then stated to be 19 feet higher than before : which was the position in which I find that Mr. Daniel’s barometer was placed, as I shall presently explain more fully. f Taking the thermometer at 70°, and the barometer at 30 inches, the true correction would be •114; but, according to the table attached to the barometer, it is only '098 : being a difference of '016 inch. MR. BAILY’S DESCRIPTION OF A NEW BAROMETER. 437 wholly imperceptible ; or at all events now inappreciable, since we are not informed at what temperature the relative measures were ascertained. The true formula for the correction of the expansion of the mercury alone is , m (t — 3C) A y — A 1 + m (t - 32) where m denotes, as in page 433, the absolute expansion of mercury for 1° Fahr. (= -0001001), and not the apparent expansion (= -0000857339) as assumed in the table above mentioned*. Besides this correction, there is another, which is peculiar to Mr. Daniel’s mode of constructing this barometer, and which is called the correction for the capacity of the cistern. As the height of the mercury in the cistern is constantly varying with the variation in the height of the mercury in the tube, it is necessary that the relative capacity, or contents, of the volume of the cistern and the tube should be determined ; as also some fixed point on the scale, as the zero of comparison. This has been done with great care by Mr. Daniel ; and the capacity of the cistern has been determined to be exactly --^th part of the capacity of the tube, and the neutral point fixed at 30-576 inches-f-. So that the correction for capacity is 30-576 — h “• Too The diameter of the tube is -530 inch : the correction for capillary attraction is therefore, by Laplace’s formula, + ‘006 ; and this is the value that is engraved on the front of the barometer case. The whole of the corrections therefore for Mr. Daniel’s barometer will be as fol- lows^: . _ -000100 1 {t — 32) 30-576 - h — h X i _j_ *0001001 (t - 32) ' fed •" ’006 There is a short brass scale, of about 4 or 5 inches, on which the divisions are cut : but the expansion of this would, in no possible case, cause an error of more than an unit in the third place of decimals : and as it is screwed to the wooden frame, which is * The absolute expansion of a liquid is that which is independent of the form, or expansion, of the vessel that contains it : the apparent expansion is obtained by deducting 3 times the linear expansion of the contain- ing vessel. Thus, the absolute expansion of mercury being ‘0001001, and the linear expansion of glass being •0000047887, we have ‘0001001 — ‘0000143661 = ‘0000857339 for the apparent expansion of the mercury. See my Paper on this subject in the Memoirs of the Astron. Soc. vol. i. page 383. f Fifty inches, measured in the upper part of the tube before it was sealed, raised the float in the cistern exactly half an inch. X Amongst the tables, separately printed and distributed with No. 114 of the Astron. Nach. by Professor Schumacher (as already mentioned in page 433), there is one showing the value of that part of the expression in the text which is denoted by — h x •0001001 (t — 32) -, for every ^ inch from 27| to 31 inches; and 1 + -0001001 (t - 32) for every degree of Fahrenheit from 6° to 88°. And this is the table that should be used for barometers of the ordinary construction, not furnished with a brass scale extending the whole length of the tube. But I am not aware that any such table has been published in this country. 3 l 2 438 MR. BAILY’S DESCRIPTION OF A NEW BAROMETER. liable to expand and contract with different degrees of moisture, independent of the temperature, no correction for this purpose can be depended upon. This is a great imperfection in the mode of constructing and fixing the scale of a barometer in- tended for very accurate purposes. The specific gravity of the mercury was ascer- tained by Mr. Faraday to be 13-624: the thermometer being at 40°, but the height of the barometer not given. I have already stated that prior to the year 1823, the registers do not indicate whether the observations have been corrected, or not ; but that, commencing with January 1823, they profess to give the corrected heights of the readings of the baro- meter, unexplained however as to the mode of correction. This continued till March 20, 1826, when a temporary suspension of the observations took place. From April 6, 1826, down to the end of the year 1836, we are again left in doubt whether the daily observations are corrected, or not. But the inference is that they were not corrected ; since we find a correction applied to the monthly means, for temperature and capillarity. I have ascertained, however, on inquiry, that the daily observations have in all cases been partially corrected : that is, the correction for the capacity of the cistern has been applied daily. Why this correction alone, on each day, should have been considered requisite, 1 have not been able to ascertain ; and as it is nowhere mentioned in the meteorological journal, it may perhaps have sometimes led to error. But leaving this part of the subject, I shall now proceed to notice the loose manner in which the remaining correction (for temperature) has been from time to time ap- plied to the monthly means. From April 6, 1826, to the end of that year, the temperature has been taken from the external thermometer, instead of the thermometer which dips into the cistern of mercury. Consequently all the reduced values of the readings are too great. By the external thermometer, I mean the thermometer which is placed outside of the building, and consequently gives the temperature of the open air. In the year 1827 this error appears to have been discovered and discontinued; but another of a different nature was at the same time introduced. For, from that epoch to the end of the year 1836, all the corrections are made under the assumption that the height of the mercury in the barometer was exactly 30 inches : when it is well known that the correction will vary according to the variation in the height. In fact there does not appear, at any time, to have been any regular and uniform system of reduction adopted. Now this state of confusion and uncertainty ought not to exist in a meteorological journal emanating from this Society, more especially as the true values are as easily attainable as the approximate ones. And although, in a general point of view, the minute differences caused by such errors may be unimportant, yet as appeals are fre- quently made to the barometer of this Society, as a standard, by persons engaged in important researches, the most scrupulous accuracy ought to be adopted and pursued, and the fullest explanation placed on record. And notwithstanding the details which MR. BAILY’S DESCRIPTION OF A NEW BAROMETER. 439 I have here given may create some doubt respecting the accuracy of the past, yet I am persuaded that the system now pursued will inspire more confidence for the future. It is on this account that I have entered thus at large on the subject: trusting that what I have here stated will not only tend to preserve for the future a more correct and uniform system, but also justify the Council in directing that the register should henceforth contain the daily observations uncorrected, and thus prevent the possibility of any similar confusion and mistakes hereafter. I shall now say a few words respecting the height of the barometer above the mean level of the sea ; a subject of much interest to many persons engaged in various pur- suits, but which appears, from the notes attached, at different periods, to the meteoro- logical journal of this Society, to be involved in some confusion and uncertainty. Thus, prior to the year 1823, the cistern of the barometer is said to be 81 feet above the level of low- water spring tides at Somerset House ; but without any information how this was connected with the sea. From 1823 to 1825, both inclusive, it is said to be 100 feet above the same level. And from 1826 to 1836, both inclusive, the above indication is omitted, and the height is said to be 83 feet 2^ inches above a fixed mark on Waterloo Bridge; or “above the mean level of the sea (presumed about) 95 feet.” The discordance between the 81 feet and the 100 feet is easily accounted for by the fact that the old barometer, prior to 1823, was fixed up in the Council-room of the Society, or the contiguous ante-room : but when Mr. Daniel’s barometer was finished, at the end of the year 1822, it was fixed up in the closet adjoining the library, on the floor which is immediately over the Council-room : the assumed difference in the elevation of the two floors (namely, 19 feet) having since been ascertained to be correct. With respect to the new reference of altitude, namely, the fixed mark at Waterloo Bridge, much doubt has frequently been expressed about its existence, since no person had been able to discover it. The fact is that there is no mark , in the common ac- ceptation of the term ; but the intended reference is nevertheless more conspicuous, more durable, and more convenient than any mark that could have been inscribed by hands. This standard mark, or level, was fixed on by Mr. Bevan in the year 1827, at the request of the Council of this Society : and the same gentleman also ascertained the difference of level between that mark and the floor of the council room. As his Report on the occasion has never yet been made public, and will throw the best light on the subject, as well as be interesting to many persons, I shall here subjoin his letter to the Council, detailing the whole circumstances of the case. “ Gentlemen, — Pursuant to the order I had the honour to receive at the close of “ your last session, I have selected a permanent and definite point of reference, or bench- “ mark, for heights at Waterloo Bridge ; and have determined the difference of level “ between this point and the floor of the Council room, in the Apartments of the “ Society at Somerset House. “ The bench-mark, I have adopted, is the surface of the granite pedestal at the 440 MR. .DAILY’S DESCRIPTION OF A NEW BAROMETER. “ base of the columns, at the north abutment of the bridge, and on the eastern side ; “ which is about five feet above the lowest platform, or landing, at the stairs. “ I have ascertained, by levelling from this spot, or bench-mark, to the floor of the “ Council room, in which the barometer was kept in June 1826, that the floor in the “centre of the doorway between the two rooms is 62-41 feet above the said bench- “ mark. The mercury, in the basin of the barometer, I found above the floor 2-84 “ feet; making the rise from the bench-mark to the mercury 65’25 feet. “ I am, Gentlemen, your obedient humble Servant, “ B. Be van.” Upon what authority it was presumed that the present position of the cistern of the barometer is ninety-five feet above the mean level of the sea, (or, in other words, that the above-mentioned station at Waterloo Bridge is 1 1 feet 9^ inches above that level) I have not been able to ascertain ; since Captain Lloyd’s levelling of the river Thames, from Sheerness upwards, as detailed in the Philosophical Transactions for 1831, ter- minated at London Bridge. He says, page 190, “I concluded my levellings at a “ standard mark sunk in the large plinth of the landing place (near the wall) of the “ stairs on the north-east side of the New London Bridge. This standard was 2’3967 “ [feet] below the north standard mark at Sheerness.” Now, as the north standard mark at Sheerness was ascertained by Captain Lloyd to be 1 3* 1 5 1 1 feet above the mean level of the sea, we consequently have the surface of the above-mentioned plinth at London Bridge equal to 10’7544 (or lOf) feet above the mean level of the sea. It therefore only remained to ascertain the difference of level between the surface of this plinth, and the surface of the plinth at Waterloo Bridge. But a doubt for a long time remained as to the position of the mark at London Bridge, since (as in the case of that at Waterloo Bridge) it had escaped the search of all those who attempted to discover it. It was at length found by Dr. Fitton, who in a note to his paper “ On the Strata below the Chalk,” inserted in vol. iv. (second series) of the Transactions of the Geological Society, page 370, gives the following ac- curate and circumstantial description of its position. “The mark here referred to is “ a flat piece of brass, let into a cavity in one of the two large flags, or slabs of gra- “ nite, which form the landing place at the bottom of the second flight of steps, de- “ scending from the footway on the north-east side of the bridge. The upper flight “ consists of 29 steps ; the second (at the foot of which is the mark) of 26. The “ lowest flight is more or less commonly covered by the water. The cavity, in which “ the mark is lodged, is about 3 inches square, with rounded angles ; and is two feet “ from the eastern wall, or side of the bridge, and two feet eight inches from the “ southern side of the stone. The surface of the brass is about half an inch beneath “ that of the stone, which is itself a few inches below the level of the water at high “ spring tides.” The propriety of such a position for a standard mark may be much questioned, since we know, from what has recently taken place at Blackfriars Bridge, that the MR. BAILY’S DESCRIPTION OF A NEW BAROMETER. 441 steps of a common landing place, abutting on the river, are liable to settle ; and in course of time to be altogether removed, for the purpose of repairs. It therefore be- came desirable, on more accounts than one, to connect together the two marks at London and Waterloo Bridges by direct levelling. This has recently been effected, at the request of the Council of this Society, by the direction and under the superin- tendence of Sir John Rennie, who readily undertook the determination of this point. In his letter on this subject, dated October 18, 1837, he says, “After repeated trials “ (the greatest variation of which did not exceed Tv of an inch) I find that the difference “ is 3 feet T65 of an inch : that is, the mark on Waterloo Bridge is 3 feet T65 of an “ inch above that on the New London Bridge fixed by Captain Lloyd.” The height of the cistern of the present barometer above the floor is 175 foot: therefore adding all these several quantities together, namely, 19-000 62-410 10-754 3-138 1-750 97052 we have, in round numbers, 97 feet for the height of the mercury in the cistern of this barometer above the mean level of the sea. One word more before I close this paper, as to the propriety of the position of the several meteorological instruments of this Society ; on which, comments have occa- sionally been made. With respect to the barometer, I am not aware that any objec- tion can be offered ; and as to the hygrometer, the observations have been found, by recent trials, not to differ materially from some expressly made in another position, at King’s College, which was considered to be more favourable for such experiments. It therefore only remains to speak of the external thermometer and of the rain-gauge ; of which all that can be said on the subject would be merely a repetition of what was justly said sixty years ago by Mr. Cavendish on a similar occasion (Philoso- phical Transactions, 1776), namely, “that, on the whole, the situation is not alto- “ gether such as could be wished, but is the best the house affords.” INDEX TO THE PHILOSOPHICAL TRANSACTIONS FOR THE YEAR 1837. A. Absorption of light, and the colours of thin plates, on the connection between, 245. Analytical operations, first memoir on the theory of, 179. Animals, on the hereditary instinctive propensities of, 365. Atmosphere, sequel to an essay on the constitution of, &c., 347. Atmospheric air, analysis of, by three methods, viz. 1. by Volta’s eudiometer, 348; 2. by nitrous gas, 350; 3. by quadrisulphuret of lime, 351. experiments on the quantity of oxygen in, from the summit of Helvellyn, Snow- don, &c., 355 et seq. B. Baily (Francis, Esq.). Description of a new barometer, recently fixed up in the apartments of the Royal Society ; with remarks on the mode hitherto pursued at various periods, and an account of that which is now adopted for correcting the observed height of the mercury in the Society’s barometer, 431. Barlow (William Henry, Esq.). On the adaptation of different modes of illuminating light- houses, as depending on their situations and the object contemplated in their erection, 211. Barometer, Description of a new one recently fitted up in the apartments of the Royal Society, &c., 431. Bevan (B. Esq.). His letter to the Council respecting the Bench-mark at W aterloo Bridge, 439. Binoxalate of potash, formula for, 50. of soda, formula for, 52. Bird (Golding). Observations on the electro-chemical influence of long-continued electric cur- rents of low tension, 37. Brain in marsupial animals, on the structure of, 87. Brewster (Sir David). On the connection between the phenomena of the absorption of light and the colours of thin plates, 245. On the development and extinction of regular doubly refracting struc- tures in the crystalline lenses of animals after death, 253. C. Chloride of copper, formula for, 71. Chlorides of manganese, — iron — magnesium and calcium, formulae for, 72. Constant {voltaic) battery of large dimensions, notice of the construction of, 160. Crystals, analytic, on, 32. explanation of some of the optical appearances of, 30. MDCCCXXXVII. 3 M Crystals, further observations on the optical phenomena of, 29. on the optical phenomena of, 25. D. Dalton (John, D.C.L.). Sequel to an essay on the constitution of the atmosphere, published in the Philosophical Transactions for 1826; with some account of the sulphurets of lime, 347. Daniell (J. Frederic, Esq.). Further observations on voltaic combinations, 141. Dispersion of light, researches towards establishing a theory of, 19. Double chloride of copper and ammonium, formula for, 73. nitrates and supernitrates, not proved to exist, 62. oxalates, on, 52. E. Electric currents of low tension, a continuous current absolutely necessary, when applied to the reduction of metallic oxides, 45. — observations on the electro-chemical influence of, 37. Equations , analysis of the roots of, 161. F. Farre (Arthur, M, B.). Observations on the minute structure of some of the higher forms of polypi, with views of a more natural arrangement of the class, 387. G. Graham (Thomas, Esq.). Inquiries respecting the constitution of salts, of oxalates, nitrates, phosphates, sulphates, and chlorides, 47. H. Height of high water, fluctuations of, due to changes in the atmospheric pressure, note on, 103. I. Insects, on the temperature of, &c., 259. temperature of, as connected with the other functions of life. 1. Respiration, 310; 2. Circulation, velocity of, 311 ; 3. Digestion, 319; 4. Gaseous, or cutaneous expenditure of the body, 319. temperature of different tribes of, viz. Melolontha vulgaris, 283 ; Melolontlia solstitialis, 285; Lucanus cervus, 286; Coccinella septernpunctata, 286; Meloe proscar abceus, and M. vio- laceus, 287 ; Gryllus viridissimus, 287 ; Staphylinus olens, and S. erythropterus, 288 ; Ca- rabus monilis, C. violaceus, and C. nemoralis , 288 ; Blaps mortisaga, 289. temperature of some which live in society. 1 . of the nests of Bornbus terrestris under observation, 294 ; 2. in its natural haunts, 295; 3. Nurse Bees, voluntary power of generating heat, 296 ; 4. Hive Bee, during winter, 299 ; 5. free heat, quantity of in the hive, 307 ; hive, mean temperature of during summer and winter, 309. temperature of the different states of, viz. larva, 264; pupa, 269; imago, 270. temperature of, as influenced by abstinence, 272 ; inactivity, 272 ; sleep, 273; hyberna- tion, 275; inordinate excitement, 280. Integral calculus , researches in, 1. Ipoh, or upas poison of the Malay peninsula, 427. J. Jones (Thomas Wharton, Esq.). On the first changes in the ova of Mammifera in consequence of impregnation, and on the mode of origin of the chorion, 339. INDEX. 445 K. Xynight (Thomas Andrew, Esq.). On the hereditary instinctive propensities of animals, 365. L. Lighthouses, on different modes of illuminating, &c., 211. Lime, quadrisulphuret of, formation of in the humid way, 354. “ table of proportions in, 355. Lime, sulphuret of, formation of in the dry way, 353. Lubbock (John William, Esq.). On the tides, 97. M. Mammifera, on the first changes in the ova of, &c., 339. Mercury, observed height of in a barometer, corrections for, to determine its absolute height, 432. specific gravity of, as determined by Dr. Prout, 432. Monobasic, bibasic, and tribasic phosphates, formula of the composition of, 63. Murphy (Rev. R.). Analysis of the roots of equations, 161. ~ ‘ ‘ First memoir on the theory of analytical operations, 179, Muscular fibre of animal and organic life, on the elementary structure of, 371. Muscular fibre of animal life, filaments, or longitudinal stria? of, 375. ‘ glutinous interior of, 377. tube of, 377. N. Newbold (Lieut. T. J.). On the ipoh, or upas poison used by the Jacoons and other aboriginal tribes of the Malay peninsula, 427. Newport (George, Esq.). On the temperature of insects, and its connection with the functions o respiiation and circulation in this class of invertebrated animals, 259. Nitrate and subnitrate of bismuth, formula? for, 60. • of copper, formulae for, 57. of magnesia, formula for, 61. of water, formula for, 56. * °f zinc, formula for, 61. O. Organic life, muscular fibre of, 380. Owen (Richard, Esq.). On the structure of the brain in marsupial animals, 87. Oxalate of ammonia, composition of, 52. of barytes, formula for, 50. ^ P°taSh 5 °f Per°Xide °fir°n andPotasM of peroxide of iron and soda, of copper and potash, formulae for, 53. of lime, formula for, 49. of magnesia, formula for, 48. of potash, formula for, 50. of soda, formula for, 52. of water, formula for, 47. of zinc, formula for, 48. 446 INDEX. P. °"on; “ . * tag**u. «. ^ ,*«,«*; 6. Notamia tori- P„w"v!: Baobn). Researches towards establishing a theory of the dispersion of Light, No. III., 19. q Quadr oxalate of potash, formula for, o I . ^ Regular doubly refracting structures, on the development and extinction of in the crystalline lenses of animals after death, 953. Salts, inquiries respecting the constitution of, &c., 4<. SkeyTfkederic C. Esq.). On the elementary structure of the muscular fibre of animal and organic life, 371. Subnitrate of copper, formula for, 58. Sulphates, formulae of the composition of some, 69. T. Taobot (H. F, Esq.). Further observations on the optical phenomena of crystals, 29. On the optical phenomena of certain crystals, 2->. _ Researches in the integral calculus. Part II. Tide, on extreme cases of great diurnal inequality of, 82. - i: es sss * : stiu «-*»"•-• progress, 79, 80. on the diurnal inequality of, at Singapore, 78. Tides, on the, 97. _ researches on the, seventh series, 75. - researches on the, eighth series, &c., 227. V. Voltaic combinations, further observations on, 144. W. WTELht(ff6the Me e“yhat HymonAaM sCpoZ'andonte mean llvel of .Jsea 75. hcght of the tide, eapec.a^es ^ ^ serfes; on the progress of the diurnal in- equality wave along the coasts of Europe^|27 PRINTED BY RICHARD AND JOHN E. TAYLOR, RED lion court, fleet street.